Poly blends with nylon

M. Marie, N. Ashuror, and C. W. Macosko, Reactive Blending of Poly- (dimethylsiloxane) with Nylon 6 and Poly (styrene) Effect of Reactivity on Morphology, Polym. Eng. Sci., 41, 631-642 (2001). 

The most common polymers used for instrument panel stmctnres are acrylonitrile-butadiene-styrene (ABS), acrylonitrile-butadiene-styrene blended with polycarbonate (ABS/PC), polycarbonate (PC), poly(phenylene oxide) blended with nylon (PPO/nylon), poly(phenylene oxide) blended with styrene (PPO/styrene), polypropylene (PP), and styrene-maleic anhydride copolymer (SMA) [3]. The percentage of each of these polymers typically used in year 2000 models is shown below in Table 17.3 [3], All of these materials by themselves... 

Mechanical testing (strain-stress, tensile strength, elongation at break, elastic modulus, melt flow, viscoelastic properties, etc), have frequently been used in the study of the photodegradation of polyethylene [711, 1656, 1704, 1750, 1957, 2124, 2128], polypropylene [1750, 1899, 1903], poly(styrene) [748], poly(styrene-co-carbon monoxide) [1429], poly(styrene-co-acrylonitrile) [747], EPDM [896], poly(vinyl chloride) [806,1137,1138,1232,1748,1938], impact modified poly(vinyl chloride) [761, 764,1232], nylon 6 [672, 726, 727, 1395,1396,2300,2305], polyethylene blends with nylon 6 [506], and polyurethanes and its blends with poly(vinyl chloride), poly(vinyl alcohol), poly(vinyl acetate) and poly(vinyl chloride-co-vinyl acetate) [652]. 

Most of the polymer s characteristics stem from its molecular stmcture, which like POE, promotes solubiUty in a variety of solvents in addition to water. It exhibits Newtonian rheology and is mechanically stable relative to other thermoplastics. It also forms miscible blends with a variety of other polymers. The water solubiUty and hot meltable characteristics promote adhesion in a number of appHcations. PEOX has been observed to promote adhesion comparable with PVP and PVA on aluminum foil, cellophane, nylon, poly(methyl methacrylate), and poly(ethylene terephthalate), and in composite systems improved tensile strength and Izod impact properties have been noted. 

Polymer Blends. Commercial blends of nylon with other polymers have also been produced in order to obtain a balance of the properties of the two materials or to reduce moisture uptake. Blends of nylon-6,6 with poly(phenylene oxide) have been most successflil, but blends of nylon-6,6 and nylon-6 with polypropylene have also been introduced. 

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). 

Engineering resins can be combined with either other engineering resins or commodity resins. Some commercially successhil blends of engineering resins with other engineering resins include poly(butylene terephthalate)—poly(ethylene terephthalate), polycarbonate—poly(butylene terephthalate), polycarbonate—poly(ethylene terephthalate), polysulfone—poly (ethylene terephthalate), and poly(phenylene oxide)—nylon. Commercial blends of engineering resins with other resins include modified poly(butylene terephthalate), polycarbonate—ABS, polycarbonate—styrene maleic anhydride, poly(phenylene oxide)—polystyrene, and nylon—polyethylene. 

In a partially crystalline homopolymer, nylon 6, property enhancement has been achieved by blending with a poly(ethylene-co-acrylic acid) or its salt form ionomer [24]. Both additives proved to be effective impact modifiers for nylon 6. For the blends of the acid copolymer with nylon 6, maximum impact performance was obtained by addition of about 10 wt% of the modifier and the impact strength was further enhanced by increasing the acrylic acid content from 3.5 to 6%. However, blends prepared using the salt form ionomer (Sur-lyn 9950-Zn salt) instead of the acid, led to the highest impact strength, with the least reduction in tensile... 

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]. 

Polycarbonate-polystyrene blend along with poly(alkylene-dicarboxylate) such as SMA SEBS copolymer for toughening blends of PPO with nylon and polyolefin (proprietary compatibilizer)... 

Marie M, Ashurov N, Macosko CW (2001) Reactive blending of poly(dimethyl silox-ane) with nylon 6 and polystyrene effect of reactivity on morphology. Poly Eng Sci 41 (4) 631—642... 

The composite systems studied by Takayanagi et al. (1980) used the polyaramides poly(p-phenylene terephthamide), PPDT, or pol.y-p-benzamide (PBA) as the reinforcing component with nylon 6 or nylon 66 as the ductile matrix polymer. Block copolymers of one of the aromatic polyamides with one of the nylon polymers were also evaluated. The blends were prepared by extruding the sulfuric acid solutions of polymers into a... 

Examples of such compatibilized systems that have been studied include EPDM/PMMA blends compatibilized with EPDM- -MMA, polypropylene/polyethylene blends with EPM or EPDM, polystyrene/nylon-6 blends with polystyrene/nylon-6 block copolymer, and poly(styrene-co-acrylonitrile)/poly(styrene-co-butadiene) blends with butadiene rubber/PMMA block copolymer. 

These systems, whose phase characteristics resemble those of the polyblends discussed in Chapter 3, can be prepared by first blending the molten polymers together until the minor component is dispersed in the form of droplets that are small in comparison to the fiber diameter desired (Allied Chemical Corp., n.d. Buckley and Phillips, 1969 Hayes, 1969 Mumford and Nevin, 1967 Papero et a/.,1967). The material is then melt-spun and drawn in order to orient both constituents and cause the dispersed phase to form elongated cylinders or fibrils. For satisfactory dispersion, the viscosities of both components must be comparable (for a discussion of rheological effects in molten polymer blends, see Section 9.6). An important biconstituent system is based on a combination of nylon 6 with a linear polyester poly(ethylene terephthalate), with nylon 6 as the continuous phase (Buckley and Phillips, 1969). As shown in Figure 9.5, fibrils of polyester... 

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