Ethylene copolymers blends

CAB Cellulose acetate-butyrate ECB Ethylene copolymer blends... 

Song et al. (2012a) prepared blends of PMMA with various functionalized poly (propylene-ethylene) copolymers. Blends were characterized by mechanical, morphological, and adhesion tests. Compatibihty was found to increase in the order of unfunctionalized poly(propylene-ethylene), MA-grafted poly (propylene-ethylene), hydroxy-grafted poly(propylene-ethylene), and secondary amine-grafted poly (propylene-ethylene) which latter species exhibited the best compatibilization efficiency. 

In some commercial, semirigid/flexible nylon formulations, an unextracted PA6 resin, which can contain up to 8 % caprolactam monomer, is used since the residual monomer can serve as a low-cost, built-in, internal plasticizer for PA6. Low-modulus, PA6/ethylene-copolymer blends (e.g., Ultramid 8254) cmitaining such low-cost nylon formulations are commercial (Table 19.23) as extrasion-grade nylons. They are used in automotive under-the-hood applications such as convoluted tubing, emission tubing, etc. 

Figure 4.17. Transmission electron microscopy images [244] of microtomed section of HIPS/PE/ethylene copolymer blend stained with RUO4 in a microwave oven, showing selective staining at the HIPS/PE interface (A). Higher magnification of HIPS region of material (B) HIPS prepared by conventional RUO4 staining (C) rubber phase appears white.

Application of the BLCT to Norbornene/Ethylene Copolymer Blends... 

Materials are also blended with VDC copolymers to improve toughness (211—214). VinyHdene chloride copolymer blended with ethylene—vinyl acetate copolymers improves toughness and lowers heat-seal temperatures (215,216). Adhesion of a VDC copolymer coating to polyester can be achieved by blending the copolymer with a linear polyester resin (217). 

Els and McGill [48] reported the action of maleic anhydride on polypropylene-polyisoprene blends. A graft copolymer was found in situ through the modifier, which later enhanced the overall performance of the blend. Scott and Macosko [49] studied the reactive and nonreactive compatibilization of nylon-ethylene-propylene rubber blends. The nonreactive polyamide-ethylene propylene blends showed poor interfacial adhesion between the phases. The reactive polyamide-ethylene propylene-maleic anhydride modified blends showed excellent adhesion and much smaller dispersed phase domain size. 

Generally, systems developed in the USA favour a combination of polyethylene with either butyl-rubber or hot-applied mastic adhesives, the latter consisting of a blend of rubber, asphalt and high molecular weight resins. In European and Far East coating plants, epoxy type primers and hard ethylene copolymer adhesives have been successfully employed. 

Blend of polypropylene and propylene ethylene copolymer Poly (ethylene terephthalate)... 

Nando, G.B. Reactive Miscible Blends from Ethylene Copolymers and Specialty Rubbers, 156th Meeting of the Rubber Division, American Chemical Society, Orlando EL, September 1999, Paper No. 55. 

Bicontinuous controlled-release matrices, poly(DL-lactic acid)-ethylene-vinyl acetate copolymer blends, 182-192... 

The efficiency of azodicarbonamide and sodium bicarbonate blowing agents for PE foams was considered (253). These systems, which generate GO2 gas, are more suitable for compression moulding of foams. Blends of the blowing agents have a reduced exotherm, so are more suitable for polymer systems that are temperature sensitive, such as ethylene copolymers. 

Journal of Applied Polymer Science 11, No.7, 15th Aug.2000, p. 1478-87 MORPHOLOGIES OF BLENDS OF ISOTACTIC POLYPROPYLENE AND ETHYLENE COPOLYMER BY RAPID EXPANSION OF SUPERCRITICAL SOLUTION AND ISOBARIC CRYSTALLIZATION FROM SUPERCRITICAL SOLUTION... 

A review is presented of the nitrogen autoclave process for the manufacture of crosslinked polyolefin foams. Process and product developments over the last few years are summarised and future possibilities are described. Process developments include use of higher temperatures and pressures to produce foams having densities as low as 10 kg/cub.m. Product developments include foams based on HDPE/LDPE blends, propylene copolymers and metallocene-catalysed ethylene copolymers. The structure and properties of these foams are compared with those of foams produced by alternative processes. 5 refs. 

Polycarbonate is blended with a number of polymers including PET, PBT, acrylonitrile-butadiene-styrene terpolymer (ABS) rubber, and styrene-maleic anhydride (SMA) copolymer. The blends have lower costs compared to polycarbonate and, in addition, show some property improvement. PET and PBT impart better chemical resistance and processability, ABS imparts improved processability, and SMA imparts better retention of properties on aging at high temperature. Poly(phenylene oxide) blended with high-impact polystyrene (HIPS) (polybutadiene-gra/f-polystyrene) has improved toughness and processability. The impact strength of polyamides is improved by blending with an ethylene copolymer or ABS rubber. 

EP ethylene-propulene amorphous copolymer blend RACO ethyl-ene-co-propylene random copolymer. 

Low density poly(ethylene) (LDPE) may have unsatisfactory heat seal properties, as they often do not provide sufficient adhesion between the sealing layers to result in a good adhesive seal for a package. Efforts to improve the heat seal characteristics of LDPE by blending them with other materials, such as ethylene copolymers with methacrylic acid or acrylic acid, have not had universal success. 

Kramer, R.H., Blomqvist, P, Hees, P.V., and Gedde, U.W. 2007. On the intumescence of ethylene-acrylate copolymers blended with chalk and silicone. Polym. Deg. Stab. 92 1899-1910. 

PVC can be blended with numerous other polymers to give it better processability and impact resistance. For the manufacture of food contact materials the following polymerizates and/or polymer mixtures from polymers manufactured from the above mentioned starting materials can be used Chlorinated polyolefins blends of styrene and graft copolymers and mixtures of polystyrene with polymerisate blends butadiene-acrylonitrile-copolymer blends (hard rubber) blends of ethylene and propylene, butylene, vinyl ester, and unsaturated aliphatic acids as well as salts and esters plasticizerfrec blends of methacrylic acid esters and acrylic acid esters with monofunctional saturated alcohols (Ci-C18) as well as blends of the esters of methacrylic acid butadiene and styrene as well as polymer blends of acrylic acid butyl ester and vinylpyrrolidone polyurethane manufactured from 1,6-hexamethylene diisocyanate, 1.4-butandiol and aliphatic polyesters from adipic acid and glycols. 

Instead of block copolymers, the use of pseudo-random linear copolymers of an aliphatic a-olefin and a vinyl aromatic monomer has been reported [20], where the styrene content of the polymer must be higher than 40 wt%. Preferred are styrene and ethylene copolymers. These blends may contain, amongst other things, an elastomeric olefinic impact modifier such as homopolymers and copolymers of a-olefins. Presumably the styrene-ethylene copolymer acts as a polymer emulsifier for the olefinic impact modifier. Using 5 wt% of an ethylene-styrene (30 70) copolymer and 20% of an ethylene-octene impact modifier in sPS, a tensile elongation (ASTM D638) of 25 % was obtained. 

Note Ethylene may be copolymerized with varying percentages of other materials, e.g., 2-butene or acrylic acid a crystalline product results from copolymerization of ethylene and propylene. When butadiene is added to the copolymer blend, a vulcan-izable elastomer is obtained. 

In addition to, or instead of, polystyrene and oils, polymers such as polypropylene, polyethylene, or ethylene-vinyl acetate copolymer can be blended with these block copolymers. Blends with S-B-S or (S-B) -X block polymers usually show greatly improved ozone resistance (S-EB-S already has excellent ozone resistance). In addition, these blends have some solvent resistance. In certain cases, some oils that are stable to UV radiation reduce the stability of the blends however, the effects can be minimized by the use of UV stabilizers and absorptive or reflective pigments (e.g., carbon black or titanium dioxide). 

Reactive PA/PBT blends acidified ethylene copolymer Sheer, 1982... 

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