Poly extrusion

Properties Nylon 6/9, molding and extrusion Nylon 6/12 Nylon 11, molding and extrusion Nylon 12, molding and extrusion Aromatic nylon (aramid), molded and unfilled Poly(amide- imide), unfilled... 

The most chemical-resistant plastic commercially available today is tetrafluoroethylene or TFE (Teflon). This thermoplastic is practically unaffected by all alkahes and acids except fluorine and chlorine gas at elevated temperatures and molten metals. It retains its properties up to 260°C (500°F). Chlorotrifluoroethylene or CTFE (Kel-F, Plaskon) also possesses excellent corrosion resistance to almost all acids and alkalies up to 180°C (350°F). A Teflon derivative has been developed from the copolymerization of tetrafluoroethylene and hexafluoropropylene. This resin, FEP, has similar properties to TFE except that it is not recommended for continuous exposures at temperatures above 200°C (400°F). Also, FEP can be extruded on conventional extrusion equipment, while TFE parts must be made by comphcated powder-metallurgy techniques. Another version is poly-vinylidene fluoride, or PVF2 (Kynar), which has excellent resistance to alkahes and acids to 150°C (300°F). It can be extruded. A more recent development is a copolymer of CTFE and ethylene (Halar). This material has excellent resistance to strong inorganic acids, bases, and salts up to 150°C. It also can be extruded. 

Because of its high cold flow, poly(vinyl acetate) is of little value in the form of mouldings and extrusions. However, because of its good adhesion to a number of substrates, and to some extent because of its cold flow, a large quantity is produced for use in emulsion paints, adhesives and various textile finishing operations. A minor proportion of the material is also converted into poly(vinyl alcohol) and the poly(vinyl acetal)s which, are of some interest to the plastics industry. 

The average molecular weight of most bulk polymerised poly(methyl methacrylates) is too high to give a material which has adequate flow properties for injection moulding and extrusion. 

Among the more than several uses for polyethers in ordn application is as a binder for extrusion cast expls (Ref 3), and in a caseless propint charge where the charge is used as an ammo element (Ref 5). Also, some development work on the use of Poly acetal resins (polyform aldehyde)1 as a fuel has been done by Singhal T ien yief 7)... 

New Poly ester-Poly ether Binder for Extrusion-Cast Explosives , UCRL-50541, UAEC, Univ of Calif (1968) Ibid, NuclSciAbst 23 (9), 17314 (1969) CA 71,71343 (1969)... 

Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT) finds some niche applications in the packaging market as amorphous, clear, extrusion, or injectionmolding material for films and bottles. 

In 2002, the world production of polymers (not including synthetic libers and rubbers) was ca. 190 million metric tons. Of these, the combined production of poly(ethylene terephthalate), low- and high-density polyethyelene, polypropylene, poly(vinyl chloride), polystyrene, and polyurethane was 152.3 milhon metric tons [1]. These synthetic, petroleum-based polymers are used, inter alia, as engineering plastics, for packing, in the construction-, car-, truck- and food-industry. They are chemically very stable, and can be processed by injection molding, and by extrusion from the melt in a variety of forms. These attractive features, however, are associated with two main problems ... 

The low thermal stability of many poly(iminocarbonates) limits the use of melt fabrication techniques such as injection molding or extrusion. For example, among all six polymers tested, only poly-(Dat-Tyr-Hex) and poly(CTTH) had low enough softening points to be compression moldable without a significant degree of thermal decomposition. ... 

Malinconico M, Immirzi B, Massenti S, La Mantia FP, Mormile P, Petti L (2002) Blends of poly-vinylalcohol and functionalized polycaprolactone. A study on the melt extrusion and post-cure of films suitable for protected cultivation. J Mat Sci 37 4973 1978 Mallek SB, Prather TS, Stapleton JJ (2007) Interaction effects of Allium spp. residues, concentrations and soil temperature on seed germination of four weedy plant species. Appl Soil Ecol 37 233-239. doi 10.1016/j.apsoil.2007.07.003... 

Rubber crumb, 10 710 Rubber extrusion, 10 710 Rubber fabrication, of poly(fluorosilicones), 20 243-244... 

Figure 6.6 Reactive extrusion block copolymer of poly(ethylene terephthalate) and polycaprolactone...

This article is an overview of the novel technology of self-reinforced LCPs with polyesters, poly(ethylene terephthalate) (PET) and poly(ethylene naphtha-late) (PEN) [10-13, 21, 23], LCP/polyester blends in a polyester matrix form in situ fibrils which improve the mechanical properties. LCPs have an inherently low melt viscosity, and provide LCP/polyester blends that effectively lower the melt viscosity during melt spinning [24], and fast injection-molding cycles. The miscibility between the LCP and polyesters can be controlled by the degree of transesterification [25] in the reactive extrusion step, and fibril formation in LCP-reinforced polyester fibers has been studied. 

ISO 580 1990 Injection-moulded unplasticized poly(vinyl chloride) (PVC-U) fittings -Oven test - Test method and basic specifications ISO 727-1 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 1 Metric series ISO 727-2 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 2 Inch-based series ISO 1163-1 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 1 Designation system and basis for specifications ISO 1163-2 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 2 Preparation of test specimens and determination of properties ISO 1265 1979 Plastics - Polyvinyl chloride resins - Determination of number of impurities and foreign particles... 

ISO 2898-1 1996 Plastics - Plasticized poly(vinyl chloride) (PVC-P) moulding and extrusion materials - Part 1 Designation system and basis for specifications ISO 2898-2 1997 Plastics - Plasticized poly(vinyl chloride) (PVC-P) moulding and extrusion materials - Part 2 Preparation of test specimens and determination of properties ISO 3114 1977 Unplasticized polyvinyl chloride (PVC) pipes for potable water supply -Extractability of lead and tin - Test method... 

ISO 7246 1984 Pipes and fittings of acrylonitrile/styrene/acrylester (ASA) - General specification for moulding and extrusion materials ISO 12092 2000 Fittings, valves and other piping system components made of unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly(vinyl chloride) (PVC-C), acrylonitrile-butadiene-styrene (ABS) and acrylonitrile-styrene-acrylester (ASA) for pipes under pressure - Resistance to internal pressure - Test method... 

Kirkpatrick, D. E., Hyun, K.S., and Chung, C.I., Friction and Its Effect on the Mechanical-to-Thermal Energy Conversion During Extrusion of Poly(Vinylidene Chloride), Polym. Eng. Set, 33, 1261 (1993)... 

S.E. Barnes, E.C. Brown, M.G. Sibley, H.G.M. Edwards and P.D. Coates, Vibrational spectroscopic and ultrasound analysis for the in-process monitoring of poly(ethylene vinyl acetate) copolymer composition during melt extrusion, Analyst, 130, 286-292 (2005). 

Blending of the lowest price commodity polymers from synthetic and carbohydrate polymer families [e.g., poly(ethylene) and starch] would appear to follow these laws. Although each polymer class is produced in large volume (first law), the production rate for com starch/synthetic polymer blends is much lower than that for the synthetic polymer this slower extrusion rate directly affects the final cost. Ignoring this limitation, the film properties of the blend are significantly poorer than those of the synthetic polymer film. Both deficiencies are related to the poor thermoplastic properties of water-soluble polymers such as cora-starch. 

Blends of poly (ethylene terephthalate) (PETP) and polypropylene (PP) with different rheological properties were dry blended or compounded, and extrusion foamed using both physical blowing and chemical agents, and the foam properties compared with those of foam produced from the individual components in the absence of compatibilisers and rheology modifiers. The foams were characterised by measurement of density, cell size and thermal properties. Low density foam with a fine cell size was obtained by addition of a compatibiliser and a co-agent, and foamed using carbon dioxide. The presence of PP or a polyolefin-based compatibiliser did not effect... 

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