Poly blended with compatibilization using

Blends with good mechanical properties can be made from DMPPO and polymers with which DMPPO is incompatible if an appropriate additive, compatibilizing agent, or treatment is used to increase the dispersion of the two phases. Such blends include mixtures of DMPPO with nylon, polycarbonate, polyester, ABS, and poly(phenylene sulfide). 

Jin et al. (65) used poly(vinylidene fluoride) (PVDF) as a compatibilizer to assist dispersion of CNTs in PMMA. Multi-walled carbon nanotubes were first coated with PVDF and then melt-blended with PMMA. Poly(vinylidene fluoride) served as an adhesive to improve wetting of CNTs by PMMA and to increase the interfacial adhesion resulting in improved mechanical properties of MWCNT-PMMA composites. 

In the context of this chapter, the use of thermoplastic starch in blends with thermoplastic resins is of the main interest. As shown in Table 16.11, several blends have been developed, e.g., with vinyl alcohol copolymers (EVAl), polyolefins, aliphatic polyesters such as poly-e-caprolactone (PCL) and its copolymers, or polymers of glycols (e.g., 1,4-butanediol) with succinic, sebacic, adipic, azelaic, decanoic or brassihc acids, PCL + PVC. Compatibilization is possible by amylose/EVAl V-type complexes, starch grafted polyesters, chain extenders like diisocyanates, epoxies, etc. [Bastioli et al., 1992, 1993]. 

PLA has also been blended with other nonbiodegradable polymers, such as poly(methyl methacrylate), acrylonitrile-butadiene-styrene, and Hytrel (from DuPont). Note that some polymers such as PE and PP are not compatible with PLA and cannot be used for compounding, unless special compatibilizers are used. 

Blends of styrenic pol5m ers (PS, high impact poly (styrene)) and biodegradable polymers (PLA) can be extruded and thermo-formed to produce very low density food service and consumer foam articles (29,31). The blends are compatibilized with styrene-based copolymers a styrene-maleic anhydride copol5mier, or a styrene methyl methacrylate copolymer. As blowing agent for foaming the compositions z-pentane is used. 

In particular, a microporous poly(/-lactide) (PLLA) composition can be prepared using poly(styrene) (PS) and as compatibilizer a copolymer from a lactide and styrene. Binary blends and compatibilized ternary blends are prepared by melt mixing the polymers and copolymer in a Brabender internal mixer with roller blades, under a constant high flow of dry nitrogen. Dry nitrogen is required to avoid a dramatic melt degradation of the PLLA. Prior to blending, PLLA and PS are dried for 48 /z in a vacuum oven at 70°C. 

Non-compatibilized blends of PS with either PEST or PEST and PMMA have been used for decorative applications or as the so-called plastic paper (Kamata et al. 1980). Similarly, PAr blends with either SAN (Brandstetter et al. 1983a, b, c) or high-performance blends of LCP with thermoplastic polymers (e.g., PP, PS, PC, PI) (Haghighat et al. 1992) showed adequate performance for the envisaged applications. However, most PS blends with engineering resins require compatibi-lization. Thus, for example, PS with PA-6 was compatibilized by addition of either methylmethacrylate-styrene copolymer (SMM) (Fayt et al. 1986b) or SMA (e.g., used in PARA/PS blends) (Lee and Char 1994). POM was blended with a small amount of either PS poly(a-methyl styrene) (MPS) or SAN and with particulate fillers (Tajima et al. 1991). PAr/PS blends were compatibilized with PAr-PS segmented copolymer (Unitika Ltd. 1983). 

Bayam and Yilmazer (2002) have reported compatibilization of poly (tetramethylene ether glycol) with SMA prepared in a batch mixer or in a TSE in the presence of zinc acetate hydrate. Blends were characterized using thermal, mechanical, morphological, and spectroscopic techniques. FTIR analysis indicated the presence of copolymer from ester formation. 

Polypropylene, 55-90 wt% PP, was blended with poly (1-butene), PB, as a dispersed phase and optionally with up to 10 wt% of low-MW poly(a-olefin-co-ethylene) plastomer compatibilizer. The blends were useful for manufacturing fibers and nonwovens, with good hand and tensile strength ... 

In order to obtain materials stable with good properties, the blends have to be compatibilized. In this work, we have investigated the effects of the compatibilization on the structure, rheological, and mechanical properties of blends of PET and PP. The compatibilizer used in this study is a triblock copolymer consisting of polystyrene end-blocks and poly(ethylene-butylene) mid-blocks grafted with maleic anhydride, MA-g-SEBS. This copolymer was already used to compatibilize other blends of polar and apolar polymers with satisfactory results. 

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