Diisocyanate coupling agents

Dogan et al. (2013) prepared blends of poly(lactic acid) with TPU through addition of 1,4-phenylene diisocyanate coupling agent. Characterization techniques included mechanical, thermal, morphological, and rheological properties. 

Some early work on copolymer-compatibilized PPE-PPS blends is summarized in Arashiro et al. (1992). PPE-PPS blends have also been compatibilized through copolymer formation between citric acid-functionalized PPE (e.g., 162 parts) and PPS (e.g., 225-275 parts) in the presence of a multifunctional epoxy resin (0-17.5 parts) and a minor amount of PBT (25-50 parts) (Brown et al. 1997a) or in the presence of a epoxy-functionalized PO and a catalyst (Brown et al. 2001) or in the presence of a bifunctional cyclic ortho ester compound (Brown et al. 1998a). See also Dekkers (1989) and Inoue et al. (1990). Okabe et al. (1989) have prepared compatibilized blends comprising PPE-g-MA and amine-functionalized PPS in the presence of 4,4 -diphenylmethane diisocyanate coupling agent. 

In a similar way, polyester block copolymers were obtained by reacting acid chloride-terminated polyesters with hydroxy-terminated polyethers,401 or by reacting polyester-containing polymer mixtures with coupling agents such as diisocyanates.402... 

Sanderson [2] prepared the energetic thermoplastic elastomer poly(3,3-bis (azidomethyl)-oxetane), (II), for use as a binder for a propellant, explosive, or gas generant for a supplemental restraint system in automobiles. Random block copolymers of poly(azidomethyloxirane) and poly(3,3-bis(azidomethyl)oxe-tane), (III), were also prepared by Sanderson [3] using toluene diisocyanate as the coupling agent. 

Lee and Wang [80] investigated the effects of lysine-based diisocyanate (LDI) as a coupling agent on the properties of biocomposites from PLA, poly (butylene succinate) (PBS) and bamboo fiber (BF). They observed that the tensile properties, water resistance, and interfacial adhesion of both PLA/BF and PBS/BF composites were improved by the addition of LDI, but thermal flow [81] was hindered due to cross-linking between polymer matrix and BF. Enzymatic biodegradability of... 

PA/TPU blends have been compatibilized by addition of abis-isocyanate coupling agent that is capable of reacting with nucleophiUc end-groups on both polymers to form a block copolymer. Franke et al. (1993) have extruded PA-6 (20-0 parts) with polyester-urethane (78-100 parts) using a TSE at 230 °C in the presence of 0.5-2 parts diphenylmethane diisocyanate. The coupling agent was added downstream of the extmder feed throat. The blends were characterized by TEM, SEC, DSC, DMA, and FTIR. 

As a continuation of the above research, Supri and Ismail used diisocyanate-polyhy-droxyl groups as a coupling agent on low-density polyethylene/acrylonitrile butadiene styrene/water hyacinth fiber (LDPE/ABS/WHF) composites [47]. Ihe coupling agent was reported to enhance the tensile strength and modulus. Moreover, it also improved the thermal stability of the composites. 

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