Structure and Properties of Tough Thermoplastic Starch Modified with Polyurethane Microparticles

Starch-based isocyanate- and non-isocyanate polyurethane hybrids: A review on synthesis, performance and biodegradation

The challenges related to the persistence of plastics in natural ecosystems fostered strong interest in developing biodegradable bioplastics. Among natural biopolymers, starch gained both academic and industrial interest owing to its impressive physicochemical properties. The use of starch in production of polyurethane (PU) composites not only yields PUs with outstanding mechanical properties but also makes the final PU products biodegradable. The hydrophilic nature of starch limits its dispersion in hydrophobic PU polymers, although it is a significant benefit in creating starch-embedded non-isocyanate polyurethane (NIPU) composites. We present a comprehensive overview to highlight important strategies that are used to improve the compatibility of starch with various PU matrices. This review also gives an overview of the recent advances in the synthesis of starch-NIPU hybrids. Moreover, we aim to deliver critical insight into strategies that boost the biodegradation characteristics of PUs along with a discussion on various methods to assess their biodegradation.

Super-tough PVC/CPE composites: an efficient CPE network by an MGA copolymer prepared through a vibro-milling process

Vibro-milling, a solid-phase mechanochemistry method, was used to prepare an amphiphilic composite particle, which is referred to as MGA. The Molau test, Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) results indicated that the core-shell structure of the acrylic impact modifier, acrylate core-shell rubber (ACR), was destroyed after vibro-milling. The ACR core was exposed and reacted with polyvinyl chloride (PVC) chains. Using 1.75 parts per hundred rubber (phr) MGA instead of 1.25 phr MC and 0.5 phr ACR, a significant enhancement effect was achieved. The notched impact strength of the PVC composites increased from 4.24 kJ m^-2 for neat PVC and 23.79 kJ m^-2 for C7A0.5MC1.25 to 65.5 kJ m^-2 for C7M1.75. Additionally, the tensile strength and elongation at break of the PVC composites were enhanced. Studies using a variety of characterization techniques show that the addition of MGA can promote the formation of an intermingled and riveted structure, and thus increase interfacial interactions and the effects of stress transfer, releasing the planar strain. The introduction of MGA can also induce the chlorinated polyethylene (CPE) phase to form a network structure at a lower CPE content, which contributes to networking and crazing and is the main toughening mechanism.

Sustainable starch modified polyol based tough, biocompatible, hyperbranched polyurethane with a shape memory attribute

Starch modified polyol based tough, biodegradable, biocompatible hyperbranched polyurethane with excellent thermoresponsive shape memory behavior near body temperature was demonstrated.

Preparing thermoplastic polyurethane/thermoplastic starch with high mechanical and biodegradable properties

This study focused on achieving biodegradable thermoplastic polyurethane (TPU) blends with good mechanical properties by the incorporation of starch.