High Biobased Carbon Content Polyurethane Dispersions Synthesized from Fatty Acid-Based Isocyanate

Evaluation of 2,3-butanediol derived from whey fermentation as an effective bio-based monomer for waterborne polyurethane dispersions

Within the context of the circular economy, the transformation of agri-food waste or by-products into valuable products is essential to promoting a transition towards more sustainable and efficient utilisation of resources. Whey is a very abundant by-product of dairy manufacturing. Apart from partial reutilisation in animal feed or some food supplements, the sustainable management and disposal of whey still represent significant environmental challenges. In this work, whey is considered a valuable resource for producing high-value products, specifically 2,3-butanediol (2,3-BDO), which was produced through fermentation using the bacterial strain Lactococcus lactis 43103. The described process yielded a >90% purity of 2,3-BDO, which was evaluated as a potential chain extender in the synthesis of bio-based waterborne polyurethane dispersions (PUDs). The incorporation of whey-derived 2,3-BDO led to the development of PUDs with up to 90% bio-based content without detrimental effects on the process or liquid-phase properties. The combination of 100% bio-based polyether polyols with partially renewable L-lysine ethyl ester diisocyanate and whey-derived 2,3-BDO as a chain extender generated totally stable, low-particle-size water dispersions of amorphous polymers characterised by similar structure and molecular weight compared to those of alternative petroleum-based PUDs. These results open up the possibility of incorporating fermentation-derived 2,3-BDO as a totally renewable component in bio-based PUDs as potential sustainable resinous systems for further formulation of water-based coatings or adhesives.

Organic-Inorganic Hybrid Materials from Vegetable Oils

The production of materials based on fossil resources is yielding more sustainable and ecologically beneficial methods. Vegetable oils (VO) are one example of base materials whose derivatives rival the properties of their petro-based counterparts. Gaps exist however and one way to fill them is by employing sol-gel processes to synthesize organic-inorganic hybrid materials, often derived from silane/siloxane compounds. Creating Si─O─Si inorganic networks in the organic VO matrix permits the attainment of necessary strength, among other property enhancements. Consequently, many efforts have been directed to optimally achieve organic-inorganic hybrid materials with VOs. However, compatibilization is challenging, and desirable conditions for matching the inorganic filler in the organic matrix remain a key stumbling block toward wider application. Therefore, this review aims to detail recent progress on these new hybrids, focusing on the main strategies to polymerize and functionalize the raw VO, followed by routes highlighting the addition of the inorganic fillers to obtain desirable composites.

Impact of microplastic residues from polyurethane films on crop growth: Unraveling insights through transcriptomics and metabolomics analysis

The utilisation of coated controlled-release fertilizers (CRFs) leads to the persistence of residual plastic films in agricultural soils, posing a potential threat to crop health. This study investigates the impacts of four residual films (0.39 %, w/w) derived from CRFs in soil, including petrochemical polyether, bio-based polyether, castor oil polyester, and wheat straw polyester polyurethane on wheat growth. This study found that PecPEUR significantly reduced wheat plant height, stem diameter, leaf area, and aboveground fresh weight by 24.8 %, 20.2 %, and 25.7 %. Through an in-depth exploration of transcriptomics and metabolomics, it has been discovered that all residual films disrupted glycolysis-related metabolic pathways in wheat roots, affecting seedling growth. Among them, PecPEUR significantly reduced the fresh weight of aboveground parts by 20.5 %. In contrast, polyester polyurethane residue had no discernible impact on aboveground wheat growth. This was attributed to the enrichment of wheat root genes in jasmonic acid and γ-aminobutyric acid metabolic pathways, thus mitigating oxidative stress, enhancing stress resistance, and ensuring normal plant growth. This study, for the first time, provides comprehensive insights into the effects of polyurethane film residue on wheat seedling growth, underscoring its potential as a promising alternative to conventional plastics in soil.

Bio-Based 2K PU Coating for Durable Textile Applications

Polyurethane (PU) coatings are often applied on high added value technical textiles. To date, most PU textile coatings are solvent based or water based. Recent advances are made in applying high solid and two-component (2K) PU on textiles. Currently, polymers made from renewable raw materials are experiencing a renaissance, owing to the trend to reduce CO2 emissions and switch to CO2-neutral renewable products. There is also the tendency towards the “bio, eco, natural” consciousness-awakening of the end consumer and the market-driven question to implement renewable materials. However, the application of bio-based coatings on textiles is limited. In this regard, the present study is conducted to develop bio-based 2K PU coating specifically designed for waterproof textiles. A 2K PU coating formulation, composed of bio-based polyol and bio-based isocyanate Desmodur Eco N7300, was made and directly applied on a polyester fabric prior to thermal curing in an oven. The coating was characterized via Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The coatings were not thermoplastic and had a glass transition temperature of approximately 50 °C. Since a bio-based pentamethylene diisocyanate trimer (PDI-trimer), Desmodur Eco N7300 was used as an isocyanate source and not a diisocyanate derivative, and the resulting bio-based 2K coating was a thermoset instead of a thermoplastic. The effect of the additives and content of isocyanate on the elongation and stress at break was studied by performing tensile tests (ISO 13934-1) on 50 µm 2K PU films and comparing the obtained values. The performance of the coating was studied by evaluating the resistance to hydrostatic pressure initially and after washing, the Q-panel Laboratory UltraViolet (QUV) aging and the hydrolysis test. The developed bio-based 2K PU coating had excellent hydrostatic pressure, QUV aging resistance, hydrolysis resistance and wash fastness at 60 °C.

Bio-Based Waterborne PU for Durable Textile Coatings

Polyurethane (PU) coatings are often applied on high added value technical textiles. Key factor to success of PU coatings is its versatility and durability. Up to today most PU textile coatings are solvent-based or water-based. Recent advances are made in applying bio-based PU on textiles. Currently, polymers made from renewable raw materials are experiencing a renaissance, owing to the trend to reduce CO₂ emissions, the switch to CO₂-neutral renewable products and the depletion of fossil resources. However, the application of bio-based coatings on textiles is limited. The present paper discusses the potential of a bio-based anionic PU dispersion as an environment friendly alternative for petroleum-based PU in textile coating. Coatings were applied on textile via knife over roll. The chemical, thermal and mechanical properties of the bio-based PU coating were characterised via FT-IR, thermogravimetric analysis, differential scanning calorimetry and tensile test. The performance of the coating was studied by evaluating antimicrobial properties, fire retardancy, the resistance to hydrostatic pressure initially and after washing, QUV ageing and hydrolysis test. The developed bio-based PUD coating complied to the fire retardancy test ISO 15025 and exhibited excellent hydrostatic pressure, QUV ageing resistance, hydrolysis resistance, wash fastness at 40 °C.

Organic-inorganic hybrid coating materials derived from renewable soybean oil and amino silanes

Novel organic–inorganic hybrid coating materials were developed using amino silanes and acetoacetylated soybean oil. The acetoacetylated soybean oil was prepared from soybean oil (a renewable resource) using a solvent-free method involving a thiol–ene and transesterification reactions, and the chemical structure was characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) spectroscopy, and viscosity analyses. On the basis of the acetoacetylated soybean oil, several organic–inorganic hybrid coating materials were prepared using different amino silanes by a catalyst-free method involving one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique), and their crosslinked structures were determined from their FT-IR and solid-state ²⁹Si NMR spectra. The resulting coating materials have good mechanical/chemical performance. This method for preparing renewable organic–inorganic hybrid coating materials may have wide uses because plant oils contain many unsaturated C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> C bonds and easy access to acetoacetate functional groups.

A novel coating material was synthesized in one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique).

High-Performance, UV-Curable Crosslinked Films via Grafting of Hydroxyethyl Methacrylate Methylene Malonate

Thermoset coatings have been used extensively to protect and enhance the appearance of substrates for industrial maintenance and architectural applications. Here, we demonstrate that anionic polymerization can be used to first graft hydroxyethyl methacrylate methylene malonate (HEMA-MM) onto a latex particle at ambient conditions, while subsequent ultraviolet (UV) exposure enabled their crosslinking into robust coatings. At room temperature, in the presence of air and water, the polymerization of HEMA-MM was initiated by anionic carboxyl groups present on the MAA latex particles and subsequently grafted onto the surface of particles. The pendent hydroxyethyl methacrylate (HEMA) group enabled UV-curing via free radical polymerization and the formation of a crosslinked network. Systematic investigations were conducted to study the formation and performance of the crosslinked coatings as a function of HEMA-MM incorporation. The incorporation of 10 wt% HEMA-MM into MAA latex yielded crosslinked coatings with decreased swelling, a heightened glass transition temperature (by ~20 °C) and a 2.9-fold improvement in the Young's moduli compared to controls (without HEMA-MM). Here, we demonstrate a facile method that provides a one-step grafting-functionalization approach using functional methylene malonates to produce UV-curable and high-performance coatings at room temperature and under atmospheric environments.

Properties of Novel Polyesters Made from Renewable 1,4-Pentanediol

Novel polyester polyols were prepared in high yields from biobased 1,4-pentanediol catalyzed by non-toxic phosphoric acid without using a solvent. These oligomers are terminated with hydroxyl groups and have low residual acid content, making them suitable for use in adhesives by polyurethane formation. The thermal behavior of the polyols was studied by differential scanning calorimetry, and tensile testing was performed on the derived polyurethanes. The results were compared with those of polyurethanes obtained with fossil-based 1,4-butanediol polyester polyols. Surprisingly, it was found that a crystalline polyester was obtained when aliphatic long-chain diacids (>C12 ) were used as the diacid building block. The low melting point of the C12 diacid-based material allows the development of biobased shape-memory polymers with very low switching temperatures (<0 °C), an effect that has not yet been reported for a material based on a simple binary polyester. This might find application as thermosensitive adhesives in the packaging of temperature-sensitive goods such as pharmaceuticals. Furthermore, these results indicate that, although 1,4-pentanediol cannot be regarded as a direct substitute for 1,4-butanediol, its novel structure expands the toolbox of the adhesives, coatings, or sealants formulators.