1
|
Vahdati M, Hourdet D, Creton C. Soft Underwater Adhesives based on Weak Molecular Interactions. Prog Polym Sci 2023. [DOI: 10.1016/j.progpolymsci.2023.101649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
|
2
|
Duigou-Majumdar A, Cortet PP, Poulard C. Debonding of a soft adhesive fibril in contact with an elastomeric pillar. SOFT MATTER 2022; 18:5857-5866. [PMID: 35904067 DOI: 10.1039/d2sm00532h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The debonding criterion of fibrils of soft adhesive materials is a key element regarding the quantitative modelisation of pressure sensitive adhesive tapes' peeling energy. We present in this article an experimental study of the detachment of a commercial acrylic adhesive tape from the top surface of a single micrometric pillar of PDMS elastomer. During an experiment, the pillar and the adhesive, after being put in contact, are separated at a constant displacement rate, resulting in the formation, the elongation and the final detachment of a fibril of adhesive material. A systematic study allows us to uncover power laws for the maximum force and the critical elongation of the fibril at debonding as a function of the diameter of the cylindrical pillar which controls the diameter of the fibril. The scaling law evidenced for the critical elongation appears as a first step toward the understanding of the debonding criterion of fibrils of soft adhesive materials. In addition, viscoelastic digitation at the triple debonding line is observed during detachment for large pillar diameters. The wavelength and penetration length of the fingers that we report appear to be consistent with existing models based on pure elastic mechanical response.
Collapse
Affiliation(s)
- Aymeric Duigou-Majumdar
- Université Paris-Saclay, CNRS, FAST, 91405, Orsay, France.
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405, Orsay, France.
| | | | - Christophe Poulard
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405, Orsay, France.
| |
Collapse
|
3
|
Rheology and Tack Properties of Biodegradable Isodimorphic Poly(Butylene Succinate)-Ran-Poly(e-Caprolactone) Random Copolyesters and Their Potential Use as Adhesives. Polymers (Basel) 2022; 14:polym14030623. [PMID: 35160612 PMCID: PMC8839382 DOI: 10.3390/polym14030623] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 02/04/2023] Open
Abstract
The sole effect of the microstructure of biodegradable isodimorphic poly(butylene succinate)-ran-poly(ε-caprolactone) random copolyesters on their rheological properties is investigated. To avoid the effect of molecular weight and temperature, two rheological procedures are considered: the activation energy of flow, Ea, and the phase angle versus complex modulus plots. An unexpected variation of both parameters with copolyester composition is observed, with respective maximum and minimum values for the 50/50 composition. This might be due to the peculiar chain configurations of the copolymers that vary as a function of comonomer distribution within the chains. The same chain configuration variations are responsible for the isodimorphic character of the copolymers in the crystalline state. Tack tests, performed to study the viability of the copolyesters as environmentally friendly hot melt adhesives (HMA), reveal a correlation with rheological results. Tackiness parameters, particularly the energy of adhesion obtained from stress-strain curves during debonding experiments, are enhanced as melt elasticity increases. Based on the carried-out analysis, the link microstructure-rheology-tackiness is established, allowing selecting the best performing HMA sample considering the polymer chemistry of the system.
Collapse
|
4
|
Effect of Service Temperature on Mechanical Properties of Adhesive Joints after Hygrothermal Aging. Polymers (Basel) 2021; 13:polym13213741. [PMID: 34771300 PMCID: PMC8587949 DOI: 10.3390/polym13213741] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/21/2021] [Accepted: 10/24/2021] [Indexed: 11/26/2022] Open
Abstract
Polyurethane adhesive and aluminum alloy were selected to make adhesive joints. Butt joints tested at different loading angles (0°, 45°, and 90°) using a modified Arcan fixture were selected to represent three stress states (normal stress, normal/shear combined stress, and shear stress, respectively). Firstly, the accelerated aging tests were carried out on the joints in a hygrothermal environment (80 °C/95% RH). The quasi-static tests were carried out at different temperatures (−40 °C, 20 °C, and 80 °C) for the joints after hygrothermal aging for different periods. The variation rules of the joints’ mechanical properties and failure modes with different aging levels were studied. The results show that the failure load of the joints was obviously affected by stress state and temperature. In the low-temperature test, the failure load of the joints decreased most obviously, and the BJ was the most sensitive to temperature, indicating that the failure load decreased more with the increase of the normal stress ratio in the joint. Through macroscopic and SEM analysis of the failure section, it was found that the hydrolysis reaction of polyurethane adhesive itself and the interface failure of the joints were the main reasons for the decrease of joint strength. The failure models were established to characterize the adhesive structure with different aging levels at service temperature.
Collapse
|
5
|
Takahashi K, Oda R, Inaba K, Kishimoto K. Scaling effect on the detachment of pressure-sensitive adhesives through fibrillation characterized by a probe-tack test. SOFT MATTER 2020; 16:6493-6500. [PMID: 32597435 DOI: 10.1039/d0sm00680g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This study extensively investigates the fibrillation process of a pressure-sensitive adhesive (PSA) using a probe-tack test. It was conducted using a glass sphere at the millimeter scale for various thicknesses of PSA layers laminated on a glass substrate, on various contact areas. A sharp decrease in the adhesion force caused by cavity growth was confirmed in the case of large contact areas, whereas cavities were not generated in the case of small contact areas on the thick PSA layer. Furthermore, an atomic force microscopy (AFM) cantilever was used to conduct a probe-tack test on considerably smaller contact areas at the micrometer scale, to focus on the fibrillation process by avoiding the cavity-growth. The transition of the adhesion force during the release process by the AFM cantilever was confirmed to resemble the transition in the fibrillation process obtained using the glass sphere by the repeated tests using the probe without cleaning the surface. The fully adhesive failure was also confirmed by the tests at sufficiently high release velocity. A comparison of these tests at different scales revealed that the detachment force from the probe at the millimeter scale is proportional to the contact area, and determined using the release-strain rate through elongation of the entire thickness of the PSA layer. By contrast, the detachment force from the AFM cantilever is proportional to the contact radius and determined using the release velocity regardless of the PSA thickness.
Collapse
Affiliation(s)
- Kosuke Takahashi
- Division of Mechanical and Space Engineering, Hokkaido University, N13, W8, Kita-ku, Sapporo, 060-8628, Japan.
| | - Ryuto Oda
- Department. of Transdisciplinary Science and Engineering, Tokyo Institute of Technology, 2-12-1 I6-10, Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Kazuaki Inaba
- Department. of Transdisciplinary Science and Engineering, Tokyo Institute of Technology, 2-12-1 I6-10, Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Kikuo Kishimoto
- Department. of Transdisciplinary Science and Engineering, Tokyo Institute of Technology, 2-12-1 I6-10, Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| |
Collapse
|
6
|
Vahdati M, Ducouret G, Creton C, Hourdet D. Thermally Triggered Injectable Underwater Adhesives. Macromol Rapid Commun 2020; 41:e1900653. [DOI: 10.1002/marc.201900653] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 01/30/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Mehdi Vahdati
- Soft Matter Sciences and EngineeringESPCI ParisPSL UniversitySorbonne UniversityCNRS F‐75005 Paris France
| | - Guylaine Ducouret
- Soft Matter Sciences and EngineeringESPCI ParisPSL UniversitySorbonne UniversityCNRS F‐75005 Paris France
| | - Costantino Creton
- Soft Matter Sciences and EngineeringESPCI ParisPSL UniversitySorbonne UniversityCNRS F‐75005 Paris France
| | - Dominique Hourdet
- Soft Matter Sciences and EngineeringESPCI ParisPSL UniversitySorbonne UniversityCNRS F‐75005 Paris France
| |
Collapse
|
7
|
Euchler E, Bernhardt R, Schneider K, Heinrich G, Wießner S, Tada T. In situ dilatometry and X-ray microtomography study on the formation and growth of cavities in unfilled styrene-butadiene-rubber vulcanizates subjected to constrained tensile deformation. POLYMER 2020. [DOI: 10.1016/j.polymer.2019.122086] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
8
|
Cavitation in thin films of amorphous polymers from the static melt induced by thermal treatment. Polym J 2019. [DOI: 10.1038/s41428-019-0173-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
9
|
Callies X, Ressouche E, Fonteneau C, Ducouret G, Pensec S, Bouteiller L, Creton C. Effect of the Strength of Stickers on Rheology and Adhesion of Supramolecular Center-Functionalized Polyisobutenes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:12625-12634. [PMID: 30260654 DOI: 10.1021/acs.langmuir.8b02533] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In order to systematically investigate the effect of the strength of the supramolecular interactions on the debonding properties of associative polymers, a series of model systems have been characterized by probe-tack tests. These model materials, composed of linear and low dispersity poly(isobutylene) chains ( Mn ≈ 3 kg/mol) center-functionalized by a single bis-urea sticker, are able to self-assemble by four hydrogen bonds. Three types of stickers are used in the present study: a bis-urea with a methylene diphenyl (MDI) spacer, a bis-urea with a tolyl (TOL) spacer, and a bis-urea with a xylyl (XYL) spacer. In order to investigate the influence of stickers in depth, both the nanostructure of the materials and the linear rheology were investigated by small-angle X-ray scattering (SAXS) and oscillatory shear, respectively. For two types of stickers (TOL and XYL), the association of polymers via hydrogen bonds induces the formation of bundles of rodlike aggregates at room temperature and the behavior of a soft elastic material was observed. For bis-urea MDI, no structure is detected by SAXS and a Newtonian behavior is observed at room temperature. In probe-tack experiments, all these materials show a cohesive mode of failure, a signature of flowing materials as previously observed for tri-urea center-functionalized poly(butylacrylate) (PnBA3U). However, XYL center-functionalized polyisobutene shows much higher debonding energies than PnBA3U, revealing the importance of the strength of noncovalent bonds in the scission/recombination dynamics. On the basis of the analysis of the debonding images, this effect is discussed via the mechanical behavior at large deformation.
Collapse
Affiliation(s)
- X Callies
- Laboratoire de Sciences et Ingénierie de la Matière Molle, CNRS, ESPCI Paris, PSL Research University , 10 rue Vauquelin , 75005 Paris , France
- Laboratoire Sciences et Ingénierie de la Matière Molle , Sorbonne-Université , 10 rue Vauquelin , 75005 Paris , France
| | - E Ressouche
- Sorbonne Université, CNRS, IPCM, Chimie des Polymères , F-75005 Paris , France
| | - C Fonteneau
- Sorbonne Université, CNRS, IPCM, Chimie des Polymères , F-75005 Paris , France
| | - G Ducouret
- Laboratoire de Sciences et Ingénierie de la Matière Molle, CNRS, ESPCI Paris, PSL Research University , 10 rue Vauquelin , 75005 Paris , France
- Laboratoire Sciences et Ingénierie de la Matière Molle , Sorbonne-Université , 10 rue Vauquelin , 75005 Paris , France
| | - S Pensec
- Sorbonne Université, CNRS, IPCM, Chimie des Polymères , F-75005 Paris , France
| | - L Bouteiller
- Sorbonne Université, CNRS, IPCM, Chimie des Polymères , F-75005 Paris , France
| | - C Creton
- Laboratoire de Sciences et Ingénierie de la Matière Molle, CNRS, ESPCI Paris, PSL Research University , 10 rue Vauquelin , 75005 Paris , France
- Laboratoire Sciences et Ingénierie de la Matière Molle , Sorbonne-Université , 10 rue Vauquelin , 75005 Paris , France
| |
Collapse
|
10
|
Chopin J, Villey R, Yarusso D, Barthel E, Creton C, Ciccotti M. Nonlinear Viscoelastic Modeling of Adhesive Failure for Polyacrylate Pressure-Sensitive Adhesives. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b01374] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Julien Chopin
- Laboratoire Sciences et Ingénierie de la Matière Molle, PSL Research University, UPMC Univ Paris 06, ESPCI Paris, CNRS, 10 rue Vauquelin, Cedex 05 75231 Paris, France
- Instituto de Física, Universidade Federal da Bahia, Campus Universitário de Ondina, rua Barão de Jeremoabo, BA 40210-340, Brazil
| | - Richard Villey
- Saint-Gobain Glass France, Chantereine R&D Center, 1 rue de Montluçon - BP 40103, Cedex 60777 Thourotte, France
| | - David Yarusso
- 3M Center,
3M
Company, 230-1D-15, St. Paul, Minnesota 55144-1000, United States
| | - Etienne Barthel
- Laboratoire Sciences et Ingénierie de la Matière Molle, PSL Research University, UPMC Univ Paris 06, ESPCI Paris, CNRS, 10 rue Vauquelin, Cedex 05 75231 Paris, France
| | - Costantino Creton
- Laboratoire Sciences et Ingénierie de la Matière Molle, PSL Research University, UPMC Univ Paris 06, ESPCI Paris, CNRS, 10 rue Vauquelin, Cedex 05 75231 Paris, France
| | - Matteo Ciccotti
- Laboratoire Sciences et Ingénierie de la Matière Molle, PSL Research University, UPMC Univ Paris 06, ESPCI Paris, CNRS, 10 rue Vauquelin, Cedex 05 75231 Paris, France
| |
Collapse
|
11
|
Yamaguchi T, Creton C, Doi M. Simple model on debonding of soft adhesives. SOFT MATTER 2018; 14:6206-6213. [PMID: 29911218 DOI: 10.1039/c8sm00723c] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We propose a simple theoretical model describing the debonding process of soft adhesives in the probe-tack test. In this model, the expansion dynamics of interfacial cavities is determined by the balance between the strain energy release rate and the rate-dependent fracture energy. As a result, we obtain analytical solutions for the cavity size, stress-strain curve, peak stress, strain at the peak stress, maximum strain, as well as the adhesion energy. Furthermore, we discuss the validity of our theoretical results by comparing them with experiments.
Collapse
Affiliation(s)
- Tetsuo Yamaguchi
- Department of Mechanical Engineering and International Institute for Carbon-Neutral Energy Research, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
| | | | | |
Collapse
|
12
|
Inozemtsev VA, Gamov AL, Moscalets AP. Soft to tough: ordering in and tack of polymeric materials. SOFT MATTER 2018; 14:2184-2193. [PMID: 29493692 DOI: 10.1039/c7sm02273e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the present paper, adhesive properties (in terms of practical work of adhesion, Wa, and maximum stress in probe tack test) of blends of polyvinyl pyrrolidone (PVP) with polyethylene glycol (PEG-400) are studied at different level of stretching stress, applied perpendicular to the probe. The anisotropic behavior in both directions is investigated. Upon stretching, blends of 50/50 wt% PVP-PEG demonstrate little decrease in tack and little increase in maximum debonding stress. Whereas for more cohesive blends like PVP-PEG mixtures with down to 35 wt% of PEG, a significant reduction in Wa at the size of an order of a magnitude is observed. Similar behavior is measured with a commercial product from 3M with the trade name "Command". For the first time, the anisotropy of probe tack properties of two identical strips after stretching is demonstrated via a specially designed quasi-2D setup, where the external force is applied either along or transverse the long side of the quasi-2D substrate, resulting in a significant difference in the measured probe tack curves. This phenomenon has been described by the block model, developed by Yamaguchi et al. We extended the block model by introducing the stretching stress into the model. The differences are explained by the difference in kinetics of the cavity growth between the two directions.
Collapse
Affiliation(s)
- Vladimir A Inozemtsev
- Faculty of Physics, M.V. Lomonosov Moscow State University, 1 blg. 2 Leninskie Gory, Moscow 119234, Russia
| | | | | |
Collapse
|
13
|
Karnal P, Roberts P, Gryska S, King C, Barrios C, Frechette J. Importance of Substrate Functionality on the Adhesion and Debonding of a Pressure-Sensitive Adhesive under Water. ACS APPLIED MATERIALS & INTERFACES 2017; 9:42344-42353. [PMID: 29111640 DOI: 10.1021/acsami.7b13984] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We investigate the effect of an aqueous environment on the adhesion of a model acrylic pressure-sensitive adhesive (PSA) composed of 2-ethylhexyl acrylate-co-acrylic acid. We use probe-tack adhesion measurements accompanied by in situ imaging of the contact region during bonding and debonding. Within the probe-tack tests, we use both hydrophilic (piranha and plasma treatment) and hydrophobic (C18-silanization) surface treatments to investigate the contribution of the probe's surface energy on the underwater adhesion. In examining contact formation in air and underwater, we find that the presence of water when contact is made leads to different modes of PSA relaxation and contact formation. For all probes investigated, the adhesive strength between the PSA and the probe decreases when measured underwater. Additionally, we observe that the presence of water during debonding has a more pronounced effect on the adhesive strength of the PSA when probed by a hydrophilic surface as opposed to a hydrophobic surface. Using fingering wavelength analysis, we estimate the surface energy of the PSA in situ and find that when submerged in water, the PSA has a significantly higher surface energy compared to in air. Therefore, combining the observation of different modes of contact formation, the increase in surface energy, and the importance of the surface energy of the probe, we suggest that the decrease in adhesive strength in water can be explained by the hydration of the PSA and by trapped water defects between the PSA and the probe.
Collapse
Affiliation(s)
| | | | - Stefan Gryska
- 3M Company , 3M Center, Building 201-4N-01, St. Paul, Minnesota 55144-1000, United States
| | | | - Carlos Barrios
- 3M Company , 3M Center, Building 201-4N-01, St. Paul, Minnesota 55144-1000, United States
| | | |
Collapse
|
14
|
Chaudhari N, Deshpande T, Singh YRG, Patil S, Kulkarni M, Raut J, Sharma A. Cavity shape transformation during peeling on elastic microchannel-patterned substrates filled with a viscous liquid. SOFT MATTER 2017; 13:2394-2401. [PMID: 28282091 DOI: 10.1039/c7sm00016b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Inspired by the detachment mechanics of natural adhesive pads, we studied the change in cavity shape during peel tests on a 10% cross-linked polydimethylsiloxane (PDMS) elastic microchannel filled with 1% cross-linked viscous PDMS liquid (patterned bilayer). During peeling, we explored cavity shape as a function of microchannel dimensions and correlated the dimensionless cavity shape factor (CSF) and characteristic stress decay length, K-1. The peel test on the liquid-filled elastic microchannel shows three distinct cavity-shape regimes, elliptical, circular, and binary, based on the values of CSF and K-1. Such cavity formation and shape regimes could be important for improving the design of pressure-sensitive adhesives.
Collapse
Affiliation(s)
- Nayantika Chaudhari
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| | - Tushar Deshpande
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| | - Yogesh R G Singh
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| | - Sandip Patil
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| | - Manish Kulkarni
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| | - Janhavi Raut
- Unilever R&D, 64 Main Road, Whitefield, Bangalore 560066, India
| | - Ashutosh Sharma
- Department of Chemical Engineering and Center for Nanosciences, Indian Institute of Technology, Kanpur-208016, UP, India.
| |
Collapse
|
15
|
Takahashi K, Yamagata Y, Inaba K, Kishimoto K, Tomioka S, Sugizaki T. Characterization of Tack Strength Based on Cavity-Growth Criterion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:3525-3531. [PMID: 26991212 DOI: 10.1021/acs.langmuir.5b04705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The adhesive force generated by a small short-term pressure, called tack, is measured by a probe tack test on pressure-sensitive adhesives (PSAs); the maximum force is evaluated by cavity growth at the interface between the PSA layer and the probe surface. As the PSA layer becomes thinner, it is more difficult to measure the tack with a cylindrical probe because of the uneven contact resulting from misalignment. A spherical probe is preferable to obtain reproducible contact on the PSA layer, but the contact area should be taken into account if the contact pressure affects the tack performance. Tack was measured on PSAs with various thicknesses in different contact areas to clarify their effect. The results showed that a larger contact area on a thinner PSA generated higher adhesive stress with larger strain. It was found that the maximum adhesive stress was not affected by the contact pressure, but it was strongly correlated to the contact radius divided by the PSA thickness. In addition, a video microscope observation showed that, in all of the experimental cases, the adhesive stress always reached the maximum when cavities were generated at the interface between the PSA and probe surface. Therefore, the criterion of cavity growth was introduced for the evaluation of the maximum adhesive stress. As a result, the experimental results, even at different release rates, were in good agreement with the estimation by considering the effect of confining a thin layer. Furthermore, the theoretical estimation indicated the ultimate value, which was not dependent upon the PSA thickness or contact area. It was defined as a material property, referred to as the "ultimate tack strength" of PSAs.
Collapse
Affiliation(s)
- Kosuke Takahashi
- Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology 2-12-1 I6-10 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Yuichiro Yamagata
- Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology 2-12-1 I6-10 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Kazuaki Inaba
- Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology 2-12-1 I6-10 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Kikuo Kishimoto
- Department of Mechanical Sciences and Engineering, Tokyo Institute of Technology 2-12-1 I6-10 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Shiori Tomioka
- LINTEC Corporation , 5-14-42 Nishiki-cho, Warabi-shi, Saitama 335-0005, Japan
| | - Toshio Sugizaki
- LINTEC Corporation , 5-14-42 Nishiki-cho, Warabi-shi, Saitama 335-0005, Japan
| |
Collapse
|
16
|
Creton C, Ciccotti M. Fracture and adhesion of soft materials: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:046601. [PMID: 27007412 DOI: 10.1088/0034-4885/79/4/046601] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Soft materials are materials with a low shear modulus relative to their bulk modulus and where elastic restoring forces are mainly of entropic origin. A sparse population of strong bonds connects molecules together and prevents macroscopic flow. In this review we discuss the current state of the art on how these soft materials break and detach from solid surfaces. We focus on how stresses and strains are localized near the fracture plane and how elastic energy can flow from the bulk of the material to the crack tip. Adhesion of pressure-sensitive-adhesives, fracture of gels and rubbers are specifically addressed and the key concepts are pointed out. We define the important length scales in the problem and in particular the elasto-adhesive length Γ/E where Γ is the fracture energy and E is the elastic modulus, and how the ratio between sample size and Γ/E controls the fracture mechanisms. Theoretical concepts bridging solid mechanics and polymer physics are rationalized and illustrated by micromechanical experiments and mechanisms of fracture are described in detail. Open questions and emerging concepts are discussed at the end of the review.
Collapse
Affiliation(s)
- Costantino Creton
- Sciences et lngénierie de la Matière Molle, CNRS UMR 7615, École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI), ParisTech, PSL Research Univeristy, 10 rue Vauquelin, F-75231 Paris cedex 05, France. SIMM, UPMC Univ Paris 06, Sorbonne-Universités, 10 rue Vauquelin, F-75231 Paris cedex 05, France
| | | |
Collapse
|
17
|
Mukherjee R, Sharma A. Instability, self-organization and pattern formation in thin soft films. SOFT MATTER 2015; 11:8717-8740. [PMID: 26412507 DOI: 10.1039/c5sm01724f] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The free surface of a thin soft polymer film is often found to become unstable and self-organizes into various meso-scale structures. In this article we classify the instability of a thin polymer film into three broad categories, which are: category 1: instability of an ultra-thin (<100 nm) viscous film engendered by amplification of thermally excited surface capillary waves due to interfacial dispersive van der Waals forces; category 2: instability arising from the attractive inter-surface interactions between the free surface of a soft film exhibiting room temperature elasticity and another rigid surface in its contact proximity; and category 3: instability caused by an externally applied field such as an electric field or a thermal gradient, observed in both viscous and elastic films. We review the salient features of each instability class and highlight how characteristic length scales, feature morphologies, evolution pathways, etc. depend on initial properties such as film thickness, visco-elasticity (rheology), residual stress, and film preparation conditions. We emphasize various possible strategies for aligning and ordering of the otherwise isotropic structures by combining the essential concepts of bottom-up and top-down approaches. A perspective, including a possible future direction of research, novelty and limitations of the methods, particularly in comparison to the existing patterning techniques, is also presented for each setting.
Collapse
Affiliation(s)
- Rabibrata Mukherjee
- Instability and Soft Patterning Laboratory, Department of Chemical Engineering, Indian Institute of Technology, Kharagpur, 721 302, India.
| | - Ashutosh Sharma
- Department of Chemical Engineering and Nano-science Center, Indian Institute of Technology, Kanpur, 208016, India.
| |
Collapse
|
18
|
Villey R, Creton C, Cortet PP, Dalbe MJ, Jet T, Saintyves B, Santucci S, Vanel L, Yarusso DJ, Ciccotti M. Rate-dependent elastic hysteresis during the peeling of pressure sensitive adhesives. SOFT MATTER 2015; 11:3480-3491. [PMID: 25791135 DOI: 10.1039/c5sm00260e] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The modelling of the adherence energy during peeling of Pressure Sensitive Adhesives (PSA) has received much attention since the 1950's, uncovering several factors that aim at explaining their high adherence on most substrates, such as the softness and strong viscoelastic behaviour of the adhesive, the low thickness of the adhesive layer and its confinement by a rigid backing. The more recent investigation of adhesives by probe-tack methods also revealed the importance of cavitation and stringing mechanisms during debonding, underlining the influence of large deformations and of the related non-linear response of the material, which also intervenes during peeling. Although a global modelling of the complex coupling of all these ingredients remains a formidable issue, we report here some key experiments and modelling arguments that should constitute an important step forward. We first measure a non-trivial dependence of the adherence energy on the loading geometry, namely through the influence of the peeling angle, which is found to be separable from the peeling velocity dependence. This is the first time to our knowledge that such adherence energy dependence on the peeling angle is systematically investigated and unambiguously demonstrated. Secondly, we reveal an independent strong influence of the large strain rheology of the adhesives on the adherence energy. We complete both measurements with a microscopic investigation of the debonding region. We discuss existing modellings in light of these measurements and of recent soft material mechanics arguments, to show that the adherence energy during peeling of PSA should not be associated to the propagation of an interfacial stress singularity. The relevant deformation mechanisms are actually located over the whole adhesive thickness, and the adherence energy during peeling of PSA should rather be associated to the energy loss by viscous friction and by rate-dependent elastic hysteresis.
Collapse
|
19
|
Brantseva TV, Ignatenko VY, Kostyuk AV, Kharenko AV, Smirnova NM, Antonov SV. Adhesion of liquid-crystalline polymer systems to substrates of varied roughness. POLYMER SCIENCE SERIES A 2014. [DOI: 10.1134/s0965545x14060017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
20
|
Feldstein MM, Bovaldinova KA, Bermesheva EV, Moscalets AP, Dormidontova EE, Grinberg VY, Khokhlov AR. Thermo-Switchable Pressure-Sensitive Adhesives Based on Poly(N-vinyl caprolactam) Non-Covalently Cross-Linked by Poly(ethylene glycol). Macromolecules 2014. [DOI: 10.1021/ma501191k] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mikhail M. Feldstein
- Faculty
of Physics, M. V. Lomonosov Moscow State University, Leninskie
Gory, Moscow 119991, Russia
- D. I. Mendeleyev University of Chemical Technology of Russia, 9 Miusskaya Square, Moscow 125047, Russia
- A. N.
Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28 Vavilova Street, 119991 Moscow, Russia
| | - Kermen A. Bovaldinova
- A. N.
Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28 Vavilova Street, 119991 Moscow, Russia
| | - Eugenia V. Bermesheva
- A.
V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky Prospect, 119991 Moscow, Russia
| | - Alexander P. Moscalets
- A. N.
Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28 Vavilova Street, 119991 Moscow, Russia
| | - Elena E. Dormidontova
- Institute
of Materials Science and Physics Department, University of Connecticut, 97 North Eagleville Road, Storrs, Connecticut 06269-3136, United States
| | - Valery Y. Grinberg
- A. N.
Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28 Vavilova Street, 119991 Moscow, Russia
| | - Alexei R. Khokhlov
- Faculty
of Physics, M. V. Lomonosov Moscow State University, Leninskie
Gory, Moscow 119991, Russia
- A. N.
Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28 Vavilova Street, 119991 Moscow, Russia
| |
Collapse
|
21
|
Tanguy F, Nicoli M, Lindner A, Creton C. Quantitative analysis of the debonding structure of soft adhesives. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2014; 37:3. [PMID: 24458551 DOI: 10.1140/epje/i2014-14003-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 07/31/2013] [Accepted: 01/06/2014] [Indexed: 06/03/2023]
Abstract
We experimentally investigate the growth dynamics of cavities nucleating during the first stages of debonding of three different model adhesives. The material properties of these adhesives range from a more liquid-like material to a soft viscoelastic solid and are carefully characterized by small strain oscillatory shear rheology as well as large strain uniaxial extension. The debonding experiments are performed on a probe tack set-up. Using high contrast images of the debonding process and precise image analysis tools, we quantify the total projected area of the cavities, the average cavity shape and growth rate and link these observations to the material properties. These measurements are then used to access corrected effective stress and strain curves that can be directly compared to the results from the uniaxial extension.
Collapse
Affiliation(s)
- François Tanguy
- Laboratoire de Physico-Chimie des Polymeres et Milieux Disperses, UMR7615 ESPCI-CNRS-UPMC, 10 rue Vauquelin, 75005, Paris, France
| | | | | | | |
Collapse
|
22
|
Nase J, Ramos O, Creton C, Lindner A. Debonding energy of PDMS: A new analysis of a classic adhesion scenario. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:103. [PMID: 24045983 DOI: 10.1140/epje/i2013-13103-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 07/25/2013] [Accepted: 07/26/2013] [Indexed: 06/02/2023]
Abstract
We investigated the debonding energy between confined layers of a soft elastic solid (PDMS) and a circular steel indenter in a flat punch geometry. PDMS is extensively used in applications, but also a widespread model system for fundamental research. Varying systematically the pulling speed and the viscoelastic properties, notably the modulus, we determined scaling laws for the debonding energy. We showed that the debonding energy is independent of the sample thickness. Applying a new approach and separating the crack initiation and the propagation part of the force curves, we analyzed the thickness dependence more precisely and we demonstrated that the energy to propagate the crack at given average speed does not only depend on the modulus, but also on the sample thickness.
Collapse
Affiliation(s)
- Julia Nase
- PMMH, UMR 7636, ESPCI, CNRS, Universités UPMC and Paris-Diderot, 10 rue Vauquelin, 75005, Paris, France,
| | | | | | | |
Collapse
|
23
|
Lopez A, Degrandi-Contraires E, Canetta E, Creton C, Keddie JL, Asua JM. Waterborne polyurethane-acrylic hybrid nanoparticles by miniemulsion polymerization: applications in pressure-sensitive adhesives. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:3878-3888. [PMID: 21395314 DOI: 10.1021/la104830u] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Waterborne polyurethane-acrylic hybrid nanoparticles for application as pressure-sensitive adhesives (PSAs) were prepared by one-step miniemulsion polymerization. The addition of polyurethane to a standard waterborne acrylic formulation results in a large increase in the cohesive strength and hence a much higher shear holding time (greater than seven weeks at room temperature), which is a very desirable characteristic for PSAs. However, with the increase in cohesion, there is a decrease in the relative viscous component, and hence there is a decrease in the tack energy. The presence of a small concentration of methyl methacrylate (MMA) in the acrylic copolymer led to phase separation within the particles and created a hemispherical morphology. The tack energy was particularly low in the hybrid containing MMA because of the effects of lower energy dissipation and greater cross-linking. These results highlight the great sensitivity of the viscoelastic and adhesive properties to the details of the polymer network architecture and hence to the precise composition and synthesis conditions.
Collapse
Affiliation(s)
- Aitziber Lopez
- Institute for Polymer Materials (POLYMAT) and Grupo de Ingeniería Química, Departamento de Química Aplicada, University of the Basque Country, Joxe Mari Korta Zentroa, Tolosa Etorbidea 72, 20018 Donostia-San Sebastián, Spain
| | | | | | | | | | | |
Collapse
|
24
|
Chung H, Glass P, Pothen JM, Sitti M, Washburn NR. Enhanced adhesion of dopamine methacrylamide elastomers via viscoelasticity tuning. Biomacromolecules 2010; 12:342-7. [PMID: 21182292 DOI: 10.1021/bm101076e] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a study on the effects of cross-linking on the adhesive properties of bio-inspired 3,4-dihydroxyphenylalanine (DOPA). DOPA has a unique catechol moiety found in adhesive proteins in marine organisms, such as mussels and polychaete, which results in strong adhesion in aquatic conditions. Incorporation of this functional group in synthetic polymers provides the basis for pressure-sensitive adhesives for use in a broad range of environments. A series of cross-linked DOPA-containing polymers were prepared by adding divinyl cross-linking agent ethylene glycol dimethacrylate (EGDMA) to monomer mixtures of dopamine methacrylamide (DMA) and 2-methoxyethyl acrylate (MEA). Samples were prepared using a solvent-free microwave-assisted polymerization reaction and compared to a similar series of cross-linked MEA materials. Cross-linking with EGDMA tunes the viscoelastic properties of the adhesive material and has the advantage of not reacting with the catechol group that is responsible for the excellent adhesive performance of this material. Adhesion strength was measured by uniaxial indentation tests, which indicated that 0.001 mol % of EGDMA-cross-linked copolymer showed the highest work of adhesion in dry conditions, but non-cross-linked DMA was the highest in wet conditions. The results suggest that there is an optimal cross-linking degree that displays the highest adhesion by balancing viscous and elastic behaviors of the polymer but this appears to depend on the conditions. This concentration of cross-linker is well below the theoretical percolation threshold, and we propose that subtle changes in polymer viscoelastic properties can result in significant improvements in adhesion of DOPA-based materials. The properties of lightly cross-linked poly(DMA-co-MEA) were investigated by measurement of the frequency dependence of the storage modulus (G') and loss modulus (G''). The frequency-dependence of G' and magnitude of G'' showed gradual decreases with the fraction of EGDMA. Loosely cross-linked DMA copolymers, containing 0% and 0.001 mol % of EGDMA-cross-linked copolymers, displayed rheological behavior appropriate for pressure-sensitive adhesives characterized by a higher G' at high frequencies and lower G' at low frequencies. Our results indicate that dimethacrylate cross-linking of DMA copolymers can be used to enhance the adhesive properties of this unique material.
Collapse
Affiliation(s)
- Hoyong Chung
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | | | | | | | | |
Collapse
|
25
|
Sakasegawa D, Tsuzuki T, Sugizaki Y, Goto M, Suzuki A. Effects of degree of cross-links on adhesion curves of cross-linked polymers observed by a point-contact method. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5856-5863. [PMID: 20184369 DOI: 10.1021/la903788f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The effects of degree of cross-links on the adhesion properties of polydimethylsiloxane (PDMS) were investigated with the use of a point-contact method in air at room temperature. The degree of cross-links, rho, was varied in a wide range, inducing changes in the rheology of the cross-linked PDMS from viscous solution to elastic gel, and the adhesion properties were examined by changing the separation velocity under a constant normal load and waiting period prior to separation. As a result, the adhesion force, F(A), strongly depended on rho and showed a maximum at a characteristic rho around the loss tangent (tan delta) = 1. In addition, the shapes of the adhesion curves were found to depend strongly on rho, and they were categorized into four types. The different states of cross-linked polymers, i.e., elastic-gel type, weak-gel type, and solution type, showed the different shapes. In the case of the weak gel, two types of characteristic adhesion curves were obtained, which resulted from the different separation mechanisms with and without cavitations near the surface due to the interface and cohesive failures. In the intermediate range of rho, viscous or elastic fingering was detected, which resulted in the characteristic shape of the adhesion curve. The factors determining the type of the adhesion curves are discussed in terms of the microscopic surface, bulk properties, and the different shapes of the adhesive front at the contact surface.
Collapse
Affiliation(s)
- Daisuke Sakasegawa
- Faculty of Environment and Information Sciences, Yokohama National University, Yokohama 240-8501, Japan
| | | | | | | | | |
Collapse
|
26
|
Deplace F, Carelli C, Langenfeld A, Rabjohns MA, Foster AB, Lovell PA, Creton C. Controlled sparse and percolating cross-linking in waterborne soft adhesives. ACS APPLIED MATERIALS & INTERFACES 2009; 1:2021-2029. [PMID: 20355828 DOI: 10.1021/am9003792] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The effect of low levels of cross-linking on the adhesive and mechanical properties of waterborne pressure-sensitive adhesives was investigated. We have taken advantage of a core-shell latex particle morphology obtained by emulsion polymerization to create a heterogeneous structure of cross-links without major modification of the monomer composition. The latex particles comprise a shell containing cross-linkable diacetone acrylamide (DAAM) repeat units localized on the periphery of a slightly softer core copolymer of very similar composition. Adipic acid dihydrazide was added to the latex prior to film formation to react with DAAM repeat units and affect interfacial cross-linking between particles in the adhesive films. The honeycomb-like structure obtained after drying of the latex results in a good balance between the dissipative properties required for adhesion and the resistance to creep. The characterization of the mechanical properties of the films shows that the chosen cross-linking method creates a percolating lightly cross-linked network, swollen with a nearly un-cross-linked component. With this cross-linking method, the linear viscoelastic properties of the soft films are nearly unaffected by the cross-linking while the nonlinear tensile properties are greatly modified. As a result, the long-term shear resistance of the adhesive film improves very significantly while the peel force remains nearly the same. A simple rheological model is used to interpret qualitatively the changes in the material parameters induced by cross-linking.
Collapse
Affiliation(s)
- F Deplace
- Laboratoire de Physico-Chimie des Polymeres et des Milieux Disperses, UMR 7615, UPMC, CNRS-ESPCI, 10 Rue Vauquelin, 75231 Paris Cedex 05, France
| | | | | | | | | | | | | |
Collapse
|
27
|
Feldstein MM, Kireeva PE, Kiseleva TI, Gdalin BE, Novikov MB, Anosova YV, Shandryuk GA, Singh P, Cleary GW. A new class of pressure-sensitive adhesives based on interpolymer and polymer-oligomer complexes. POLYMER SCIENCE SERIES A 2009. [DOI: 10.1134/s0965545x09070074] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
28
|
Wang T, Canetta E, Weerakkody TG, Keddie JL, Rivas U. pH dependence of the properties of waterborne pressure-sensitive adhesives containing acrylic acid. ACS APPLIED MATERIALS & INTERFACES 2009; 1:631-9. [PMID: 20355985 DOI: 10.1021/am800179y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Polymer colloids are often copolymerized with acrylic acid monomers in order to impart colloidal stability. Here, the effects of the pH on the nanoscale and macroscopic adhesive properties of waterborne poly(butyl acrylate-co-acrylic acid) films are reported. In films cast from acidic colloidal dispersions, hydrogen bonding between carboxylic acid groups dominates the particle-particle interactions, whereas ionic dipolar interactions are dominant in films cast from basic dispersions. Force spectroscopy using an atomic force microscope and macroscale mechanical measurements show that latex films with hydrogen-bonding interactions have lower elastic moduli and are more deformable. They yield higher adhesion energies. On the other hand, in basic latex, ionic dipolar interactions increase the moduli of the dried films. These materials are stiffer and less deformable and, consequently, exhibit lower adhesion energies. The rate of water loss from acidic latex is slower, perhaps because of hydrogen bonding with the water. Therefore, although acid latex offers greater adhesion, there is a limitation in the film formation.
Collapse
Affiliation(s)
- Tao Wang
- Department of Physics and Surrey Materials Institute, University of Surrey, Guildford, Surrey, United Kingdom
| | | | | | | | | |
Collapse
|
29
|
Retsos H, Lee D, Lim MY, Lee JC, Char K, Creton C. Temperature stability of the interfacial structure between a sulfonated crystalline alkyl side-chain polymer and a soft adhesive. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:10169-10173. [PMID: 18700749 DOI: 10.1021/la801043r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The fracture toughness of interfaces between a sulfonated alkyl side-chain graft copolymer and a soft acrylic random copolymer containing acrylic acid monomers was investigated with a probe test method. Interfaces between a thin (100 nm) layer of the block copolymer and a thick (100 microm) layer of the acrylic copolymer were prepared at room temperature and subsequently annealed for 7 h at different temperatures. After the annealing step, the interface was quenched to room temperature and tested, a strategy that provides the advantage of keeping constant the mechanical properties of the materials on both sides of the interface so that any major difference in adhesive behavior can only be attributed to a change in the interfacial structure. For annealing temperatures below the crystalline to liquid crystalline transition temperature (86 degrees C), the adhesion energy remained very low and failure occurred by interfacial crack propagation. However when the interface was annealed above that temperature, a much higher adhesion energy was observed at room temperature because of the formation of a fibrillar structure upon debonding. The results indicate that the crystalline order at low temperature is very stable presumably because of the strong interactions between the sulfone groups in the side chains. However, when these interactions weaken and the side chains become liquid crystalline, the surface reconstruction mechanism cannot be prevented and strong interactions formed between the polar parts of the copolymer and the acrylic acid. These strong interactions remain during the cooling step, and a mechanism of surface reconstruction is proposed.
Collapse
Affiliation(s)
- Haris Retsos
- Physico-Chimie des Polymeres et des Milieux Disperses, UMR 7615, Ecole Superieure Physique et de Chimie Industrielles, 10 rue Vauquelin, Paris, France
| | | | | | | | | | | |
Collapse
|
30
|
Glassmaker NJ, Hui CY, Yamaguchi T, Creton C. Detachment of stretched viscoelastic fibrils. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2008; 25:253-266. [PMID: 18398567 DOI: 10.1140/epje/i2007-10287-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Accepted: 02/05/2008] [Indexed: 05/26/2023]
Abstract
New experimental results are presented about the final stage of failure of soft viscoelastic adhesives. A microscopic view of the detachment of the adhesive shows that after cavity growth and expansion, well adhered soft adhesives form a network of fibrils connected to expanded contacting feet which fail via a sliding mechanism, sensitive to interfacial shear stresses rather than by a fracture mechanism as sometimes suggested in earlier work. A mechanical model of this stretching and sliding failure phenomenon is presented which treats the fibril as a nonlinear elastic or viscoelastic rod and the foot as an elastic layer subject to a friction force proportional to the local displacement rate. The force on the stretched rod drives the sliding of the foot against the substrate. The main experimental parameter controlling the failure strain and stress during the sliding process is identified by the model as the normalized probe pull speed, which also depends on the magnitude of the friction and PSA modulus. In addition, the material properties, viscoelasticity and finite extensibility of the polymer chains, are shown to have an important effect on both the details of the sliding process and the ultimate failure strain and stress.
Collapse
Affiliation(s)
- N J Glassmaker
- Laboratoire de Physico-Chimie des Polymères et Milieux Dispersés, UMR7615 ESPCI-CNRS-UPMC, 10 Rue Vauquelin, 75231, Paris Cédex 05, France
| | | | | | | |
Collapse
|
31
|
Lu ZX, Yu SW, Wang XY, Feng XQ. Effect of interfacial slippage in peel test: theoretical model. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2007; 23:67-76. [PMID: 17541502 DOI: 10.1140/epje/i2006-10078-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Accepted: 04/27/2007] [Indexed: 05/15/2023]
Abstract
Peel test is an efficient method to assess the performance and characteristics of materials such as adhesives and adhesive tapes. Recent experiments evidenced that the measured adhesive strength is closely related to the shear-induced interfacial slippage near the delamination front due to the concomitant Poisson contraction effect of the adhesive. Based on the experimental observations, a theoretical model is presented in this paper to examine the effect of the shear-induced interfacial slippage in the peel test. The influence of the interfacial slippage, represented by the shear displacement in the cohesive zone, on the fracture energy of decohesive zone is analyzed. An implicit expansion method with a Gauss-Chebyshev quadrature scheme is used to derive the solution. It is found that the length of the slippage zone and the receding contact angle of adhesives are the two most significant contributors to the total fracture energy of the decohesive zone. These results demonstrate that the mechanism of interfacial slippage plays a significant role in the adhesion and peeling behaviors of adhesives.
Collapse
Affiliation(s)
- Z X Lu
- FML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, PRC
| | | | | | | |
Collapse
|
32
|
Yamaguchi T, Doi M. Debonding dynamics of pressure-sensitive adhesives: 3D block model. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2006; 21:331-9. [PMID: 17297565 DOI: 10.1140/epje/i2006-10073-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2006] [Accepted: 01/04/2007] [Indexed: 05/13/2023]
Abstract
We develop a 3-dimensional mechanical model which describes cavity expansions in a viscoelastic solid medium during the debonding phase of the probe-tack test. The stress-strain curves are in good agreement with experiments for the typical pressure-sensitive adhesives. We also show that the separation speed dependence can be explained by viscous dissipations due to large strain rates around the cavities.
Collapse
Affiliation(s)
- T Yamaguchi
- CREST, Japan Science and Technology Agency (JST), 7-3-1 Hongo, 113-8656, Japan.
| | | |
Collapse
|
33
|
Yamaguchi T, Morita H, Doi M. Modeling on debonding dynamics of pressure-sensitive adhesives. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2006; 20:7-17. [PMID: 16733634 DOI: 10.1140/epje/i2005-10078-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Accepted: 03/08/2006] [Indexed: 05/09/2023]
Abstract
We propose a simple mechanical model describing viscoelasticity and cavitation during the debonding process in pressure-sensitive adhesives (PSA). Our calculation qualitatively reproduces typical stress-strain curves in the probe-tack test, such as the steep stress maxima and the following plateau region. It is shown that in the thin-film geometry the stress-strain curve is essentially determined by the cavities created by the large negative pressure. Effects of pre-existent air bubbles due to surface roughness are also discussed.
Collapse
Affiliation(s)
- T Yamaguchi
- CREST, Japan Science and Technology Agency, Japan.
| | | | | |
Collapse
|
34
|
Shull KR. Fracture and adhesion of elastomers and gels: Large strains at small length scales. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/polb.21005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|