Polypropylene blends with polyamide

Considerable amounts of EPM and EPDM are also used in blends with thermoplastics, eg, as impact modifier in quantities up to ca 25% wt/wt for polyamides, polystyrenes, and particularly polypropylene. The latter products are used in many exterior automotive appHcations such as bumpers and body panels. In blends with polypropylene, wherein the EPDM component may be increased to become the larger portion, a thermoplastic elastomer is obtained, provided the EPDM phase is vulcanked during the mixing with polypropylene (dynamic vulcani2ation) to suppress the flow of the EPDM phase and give the end product sufficient set. 

Polypropylene-Polyamide Blends with Compatibilizing Agents... 

Fig. 5 a Scanning elecfxon microscope SEM) micrographs of polypropylene -polyamide blends without RS (broken under liquid nitrogen), b S EM micrographs of polypropylene polyamide blends with RS (broken under liquid nitrogen)... 

Santrach [1] observed that HDT values were dependent on the amount and types of film former and lubricant. Fiber glass that has been sized for polyamide gives HDT values of about 240-252°C for nylon 6,6 levels above 50% in the polymer phase of compatibilized blends with polypropylene. However, in polypropylene type fiber glass, the HDT is only about 150-155°C. These observations are consistent with Santrach s comments about the addition of glass fibers to crystalline resins giving... 

PESA can be blended with various thermoplastics to alter or enhance their basic characteristics. Depending on the nature of thermoplastic, whether it is compatible with the polyamide block or with the soft ether or ester segments, the product is hard, nontacky or sticky, soft, and flexible. A small amount of PESA can be blended to engineering thermoplastics, e.g., polyethylene terepthalate (PET), polybutylene terepthalate (PBT), polypropylene oxide (PPO), polyphenylene sulfide (PPS), or poly-ether amide (PEI) for impact modification of the thermoplastic, whereas small amount of thermoplastic, e.g., nylon or PBT, can increase the hardness and flex modulus of PESA or PEE A [247]. 

This technology was first commercially applied to polyurethane blend [121] and patented as Rimplast (for Reactive Injection Molding), but many polymers have since been blended with polysiloxane thanks to this method polyethylene [122], polypropylene [122,123], polyamide [124-130], polyesters [128,131-133], poly(phenylene ether) [134], fluorocarbons [135] and many more. Many of them include reinforcing fillers such as fumed silica. The silicone base involved can moreover contain reactive groups such as the epoxy group [136,137]. A typical silicone base useful for these blends was de-... 

Polyamide-6 (PA-6) and polypropylene (PP) are both semi-crystalline polymers and the combination of an engineering plastic (PA) and the best commodity product (PP) could lead to new blends with Interesting Intermediate properties. We tested systems containing 50 wt% of each product and the ones obtained by addition of 3% of the reactive PP-g-AM resulting from previous continuous grafting in the extruder. The blends were prepared by simple mixing in the ZSK 30 twin-screw extruder and the samples for mechanical testing were molded by injection in a BILLION equipment. 

Some synthetic polymers like, polyurethanes, specifically polyether-polyurethanes, are likely to be degraded by microbes but not completely. However, several polymers such as, polyamides, polyfluorocarbons, polyethylene, polypropylene, and polycarbonate are highly resistant to microbial degradation. Natural polymers are generally more biodegradable than synthetic polymers specifically, polymers with ester groups like aliphatic polyesters [1]. Therefore, several natural polymers such as cellulose, starch, blends of those with synthetic polymers, polylactate, polyester-amide, and polyhydroxyalkanoates (PHAs) have been the focus of attention in the recent years [3]. 

Figure 8.12 Evolution of polypropylene (PP) morphology in blending with polyamide 6 (PAS) at various times of mixing in chaotic mixing (a) at short time, mostly lamellar (b) mostly fibrillar at intermediate stage of mixing and (c) mostly droplets at later stages of mixing [204-206].

Tchoudakov, R., Breuer, O., Narkis, M., and Siegmann, A. (1996) Conductive polymer blends with low carbon black loading polypropylene/polyamide. Polym. Eng. Sci., 36, 1336. 

Z. Yang, Z. Zhang, Y. Tao, K. Mai, Preparation, crystallization behavior, and melting characteristics of P-nucleated isotactic polypropylene blends with polyamide 6, Journal of Applied Polymer Science 112 (1) (2009) 1-8. 

Blends of polypropylene (PP) with other polymers are used widely and are of great commercial importance. Many of these are immiscible at all compositions and temperatures of interest for example, the blends of PP and polyamides (PAs) that are used in fiber applications are highly incompatible. However, recent work has shown that PP is miscible with a number of other polyolefins, and the strength of the interactions between these polymers has been measured. Here the data that have been obtained on PP blend miscibility are compiled and work on the kinetics of phase separation for such blends is described. 

Helmert, A., Champagne, M.F., Dumoulin, M.M. and Fritz, H.G. (1995) Compatibilization of polypropylene/polyamide-bb blends via reactive blending with maleated polypropylene, in Proceedings of the Conference on Polyblends 95, October 19-20, Boucher e, Canada, National Research Council Canada, BouchervUle, Canada. 

Only two classes of polypropylene (PP) blends have achieved commercial success blends wiA polyolefins and with polyamides (PA). With PP/polyolefin blends, the goal is either to improve the impact resistance of the base resin (impact-modified PPs) or to produce thermoplastic elastomers (d)mamically vulcanized blends). PA/PP blends aim at bridging the property gap between the two pol5oners. Therefore, sigitificant information on processing is available only for these two families of blends. 

Dencheva N, Denchev Z, Oliveira M J and Funari S S (2010) Microstructure studies of in situ composites based on polyethylene/polyamide 12 blends, Macromolecules 43 4715-4726. Polaskova M, Cermak R, Sedlacek T, Kalus J, Obadal M and Saha P (2010) Extrusion of polyethylene/poljTDropylene blends with microfibrillar-phase morphology, Polym Compos S1 1427-1433. Wang H, Guo J and He Y X (2011) Rheology and thermal properties of polypropylene/poly(phenyl-ene sulfide) microfibrillar composites, Adv Mater Res 194-196 1506-1509. 

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