Preparation and Characterization of Cross-Linked Poly(butylene succinate) by Multifunctional Toluene Diisocyanate–Trimethylolpropane Polyurethane Prepolymer

Production of Cyclic Anhydride-Modified Starches

Modified starches offer a biodegradable, readily available, and cost-effective alternative to petroleum-based products. The reaction of alkenylsuccinic anhydrides (ASAs), in particular, is an efficient method to produce amphiphilic starches with numerous applications in different areas. While ASAs are typically derived from petroleum sources, maleated soybean oil can also be used in an effort to produce materials from renewable sources. The reaction of gelatinized waxy maize starch with octenylsuccinic anhydride (OSA), dodecenylsuccinic anhydride (DDSA), a maleated fatty acid (TENAX 2010), phthalic anhydride (PA), 1,2,4-benzenetricarboxylic acid anhydride (trimellitic anhydride, TMA), and three maleated soybean oil samples, was investigated under different conditions. To minimize the reaction time and the amount of water required, the outcome of the esterification reaction was compared for starch dispersions in benchtop dispersed reactions, for starch melts in a heated torque rheometer, and for reactive extrusion in a pilot plant scale twin-screw extruder. The extent of reaction was quantified by ¹H NMR analysis, and changes in molecular weight and diameter were monitored by gel permeation chromatography (GPC) analysis. The outcome of the reactions varied markedly in terms of reaction efficiency (RE), molecular weight distribution, and average hydrodynamic diameter, for the products derived from the different maleated reagents used, as well as for the different reaction protocols.

A novel ionomeric polyurethane elastomer based on ionic liquid as crosslinker

A novel flexible polyurethane was prepared using ionic liquid as crosslinker. It showed lower T_g, superelastomeric behavior with very high elongation, better tensile and oil resistance properties than a non-ionic crosslinked PU or a linear PU.

Poly(lactic acid)/polypropylene and compatibilized poly(lactic acid)/polypropylene blends prepared by a vane extruder: analysis of the mechanical properties, morphology and thermal behavior

Poly(lactic acid) (PLA)/polypropylene (PP) blends with different weight fractions were prepared by a novel vane extruder. The mechanical properties, morphology, crystallization behavior and thermal stability of the blends were investigated. The tensile strength, flexural strength and elongation at break decreased nonlinearly when the PP content was not more than 50 wt% and then increased with an increase in the PP content. The flexural modulus decreased with increasing PP weight fraction. The PLA/PP 90:10 blend exhibited the optimum impact strength. Scanning electron microscopy measurements revealed that the PLA/PP blends were immiscible. Phase separation occurred significantly at a blend ratio of 50:50. Regarding the PLA/PP 90:10 blend, the mean diameter of the disperse-phase PP particles was the smallest at 1.11 μm. Differential scanning calorimetry measurements showed that low content of PP enhanced the crystallization of PLA. The PLA component in the blends impeded the crystallization of PP when PP was used as the matrix. The thermogravimetric analysis measurement involved a two-step decomposition process of the blends. The thermal resistance of the blends was improved by compounding with PP. As compatibilizers, both the maleic anhydride-grafted PP and the ethylene/n-butyl acrylate/glycidyl methacrylate terpolymer helped improve the mechanical properties, crystallization property and thermal resistance of the PLA/PP blends.