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Novel highly functional biobased epoxy compounds, epoxidized sucrose esters of fatty acids (ESEFAs), were cross-linked with a liquid cycloaliphatic anhydride to prepare polyester thermosets. The degree of cure or conversion was studied using differential scanning calorimetry (DSC), and the sol content of the thermosets was determined using solvent extraction. The mechanical properties were studied using tensile testing to determine Young's modulus, tensile stress, and elongation at break. Dynamic mechanical analysis (DMA) was used to determine glass-transition temperature, storage modulus, and cross-link density. The nanomechanical properties of the surfaces were studied using nanoindentation to determine reduced modulus and indentation hardness. The properties of coatings on steel substrates were studied to determine coating hardness, adhesion, solvent resistance, and mechanical durability. Compared with the control, epoxidized soybean oil, the anhydride-cured ESEFAs have high modulus and are hard and ductile, high-performance thermoset materials while maintaining a high biobased content (71-77% in theory). The exceptional performance of the ESEFAs is attributed to the unique structure of these macromolecules: well-defined compact structures with high epoxide functionality. These biobased thermosets have potential uses in applications such as composites, adhesives, and coatings.

Naturally occurring carboxylic acids when used as cross-linkers with a highly functional bio-based epoxy resin result in thermosets having excellent physical and mechanical properties which are also degradable. Thermosets have many important applications (coatings, composites, adhesives, etc.), but they are typically made of nondegradable, nonrenewable materials. In this paper, di-and multifunctional carboxylic acids found in fruit juices as well as other naturally available dicarboxylic acids were used to cross-link epoxidized sucrose soyate (ESS) without the use of extra catalyst or toxic compounds except for water. For the sake of understanding the mechanism of the water-assisted curing reaction between ESS and the acids, the reactivity of the natural acids toward ESS and the curing process were investigated. Water enabled the natural acids with high water solubility and acidity to be dispersed well in ESS and led to rapid cross-linking with ESS. The thermosets possessed excellent thermal and mechanical properties and displayed great potential to be utilized in fully green coatings. The thermosets could be degraded and completely dissolved in NaOH aqueous solutions very rapidlyas fast as 13 minand they could also be thermally degraded.

Background Vitamin D-binding protein (DBP) genetic polymorphisms have been associated with chronic obstructive pulmonary disease (COPD). DBP has an indirect role in macrophage activation; thus it was hypothesised that DBP is present in the airway and contributes to lung disease by this mechanism. Methods 471 PiZZ subjects with a1-antitrypsin deficiency (AATD) were genotyped for tag single nucleotide polymorphisms (SNPs) covering the DBP gene (GC), together with known functional variants, prior to seeking association with COPD phenotypes. 140 subjects with usual COPD and 480 controls were available for replication. Vitamin D and DBP levels were measured by tandem mass spectrometry and ELISA, respectively, in serum and DBP in the sol phase of sputum in a subset of 60 patients. Concentrations were related to phenotype and to alveolar macrophage activation. Results rs2070741 was associated with airway bacterial colonisation (p¼0.04) and bronchiectasis (p¼0.01), as was rs7041 (p¼0.03) which also influenced vitamin D concentrations (p¼0.01). The GC2 variant predisposed to bronchiectasis in AATD (p¼0.04) and protected against COPD (p¼0.05); the latter association was replicated in usual COPD versus controls (p¼0.04). Circulating DBP related inversely to forced expiratory volume in 1 s (FEV 1 ) (p¼0.02), in direct contrast to vitamin D, where deficiency related to low FEV 1 (p¼0.04). Sol DBP related directly to alveolar macrophage activation (p¼0.004). Conclusions The genetic association of DBP with COPD may be mediated by effects on macrophage activation, since DBP relates to FEV 1 , and affects macrophage activation. Vitamin D effects may be independent of this, relating more strongly to innate immunity.

A carboxylic acid functional trimer made from the reaction of isosorbide with maleic anhydride was used to cross-link epoxidized sucrose soyate (ESS), resulting in biobased, degradable thermosets having a good combination of hardness and flexibility. This work addresses some critical needs for thermosets such as improving the sustainability of raw materials, enabling recycling, and achieving both good material hardness and flexibility/ductility simultaneously. In this paper, a dicarboxylic acid, MI, was synthesized from isosorbide and maleic anhydride and characterized in detail by FTIR and 1 H NMR. It was utilized to cross-link ESS without using extra catalyst or toxic compounds except for ethanol and water. For comparison, a dicarboxylic acid from 1,3-propanediol and maleic anhydride (MP) was also synthesized and used to cross-link ESS. Because of the carbon−carbon double bond in conjugation with the carboxylic acid group, both MI and MP showed high reactivity toward ESS and could cross-link ESS with the assistance of water and ethanol. The MI cross-linked thermosets exhibited superior thermal and mechanical properties and excellent coating performance including a high level of flexibility (reverse impact >168 in.-lb and elongation at break from mandrel bend >28%), adhesion (5B), and solvent resistance as well as high hardness (Konig pendulum hardness 189 s). The thermosets could be degraded and completely dissolved in NaOH aqueous solution at 50 °Cas fast as 10 minbut they are stable in an HCl aqueous solution at 50 °C. The thermosets could also be thermally degraded.

Siloxane-polyurethane fouling-release (FR) coatings based on aminopropyl terminated poly(dimethylsiloxane) (PDMS) macromers were prepared and characterized for FR performance via laboratory biological assays. These systems rely on self-stratification, resulting in a coating with a siloxane-rich surface and polyurethane bulk. Previously, these coating systems have used PDMS with multiple functional groups which react into the polyurethane bulk. Here, aminopropyl terminated PDMS macromers were prepared, where a single amine group anchors the PDMS in the coating. Coatings were prepared with four molecular weights (1000, 5000, 10,000, and 15,000 g mol⁻¹) and two levels of PDMS (5% and 10%). High water contact angles and low surface energies were observed for the coatings before and after water immersion, along with low pseudobarnacle removal forces. Laboratory bioassays showed reduced biofilm retention of marine bacteria, good removal of diatoms from coatings with low molecular weight PDMS, high removal of algal sporelings (young plants), and low removal forces of live barnacles.

Renewable polymeric materials derived from biomass with built-in phototriggers were synthesized and evaluated for degradation under irradiation of UV light. Complete decomposition of the polymeric materials was observed with recovery of the monomer that was used to resynthesize the polymers.