Polyethylene chlorinated plastic

If corona, plasma, or flame treatment is chosen as the surface treatment, it is important to bond quickly after the treatment. Waiting several hours will reduce the effectiveness of the treatment. In some cases, attempts to bond 24 h after the treatment can give the same poor bonding results as if the plastic had never been surface treated. If surface oxidation is not possible, priming the surface with a chlorinated polyethylene primer is a second choice [95]. 

Chlorinated polyethylene CPEs provide a very wide range of properties from soft/ elastomeric to hard. They have inherent oxygen and ozone resistance, have improved resistance (compared to PEs) to chemical extraction, resist plasticizers, volatility, and weathering. Products do not fog at high temperatures as do PVCs and can be made flame retardant. 

About 10% of the ethylene produced in the U.S. is used to make vinyl chloride, which in the chemical trade is usually referred to as vinyl chloride monomer or VCM. The largest use of VCM is for polymerization to poly(vinyl chloride) (PVC), a thermoplastic, which in terms of volume is second only to polyethylene. PVC is used in such diverse areas as containers, floor coverings (linoleum), plastic pipes, raincoats, and many, many others. PVC has an evironmental disadvantage over non-chlorine containing plastics in that when it is disposed of by incineration it produces hydrogen chloride, which dissolves in atmospheric water to give hydrochloric acid. Polyethylene does not have this undesirable feature. 

ISO 6402-1 2002 Plastics - Acrylonitrile-styrene-acrylate (ASA), acrylonitrile-(ethylene-propylene-diene)-styrene (AEPDS) and acrylonitrile-(chlorinated polyethylene)-styrene (ACS) moulding and extrusion materials - Part 1 Designation system and basis for... 

Plastics and elastomers Degrades chlorinated polyethylene, neoprene, nitrile rubber, polysulfide, polyurethane... 

Many plastic materials are acid resistant, among them is "Teflon (polytetrafluoroethylene). This material resists acids but does not withstand high temps. "Silastic resists nitric acid well. Polyethylene plastic and chlorinated polyethylene are also good acid resistors... 

Blending of polymers is an attractive method of producing new materials with better properties. Blends of aliphatic polyesters, especially of poly(e-CL), have been investigated extensively and have been the subject of a recent review paper [170]. Poly(e-CL) has been reported to be miscible with several polymers such as PVC, chlorinated polyethylene, SAN, bisphenol A polycarbonate, random copolymers of Vdc and VC, Vdc and AN, and Vdc/VAc, etc. A single composition-dependent Tg was obtained in the blends of each of these polymers with poly(e-CL). This is of interest as a polymeric plasticizer in these polymers. Blends of PVC and poly(e-CL) with less than 50 wt % of poly(e-CL) were homogeneous and exhibited a single Tg. These blends were soft and pliable because the inherent crystallinity of poly(e-CL) was destroyed and PVC was plasticized... 

At room temperature, PE is a semi-crystalline plastomer (a plastic which on stretching shows elongation like an elastomer), but on heating crystallites melt and the polymer passes through an elastomeric phase. Similarly, by hindering the crystallisation of PE (that is, by incorporating new chain elements), amorphous curable rubbery materials like ethylene propylene copolymer (EPM), ethylene propylene diene terpolymer (EPDM), ethylene-vinyl acetate copolymer (EVA), chlorinated polyethylene (CM), and chlorosulphonated polyethylene (CSM) can be prepared. 

The incineration of DPE suits (which are made of a mixture of polyvinyl chloride, chlorinated polyethylene, resins, plasticizers, and metal stabilizers) is subject to the same dioxin emission limits at industrial incineration facilities as they are at chemical agent disposal facilities. Thus the waste feed load and incineration bum conditions for any of these chlorinated materials into incineration units may be regulated to meet air emission control requirements. These emission control limits and resulting incineration performance requirements are spelled out in the RCRA and Clean Air Act Title 5 permits for each site. 

The moderate random chlorination of polyethylene suppresses crystallinity and yields chlorinated polyethylene elastomer (CPE), a rubber-like material that can be crosslinked with organic peroxides. The chlorine (Cl) content is in the range of 36 to 42%, compared to 56.8% for PVC. Such elastomer has good heat and oil resistance. It is also used as a plasticizer for PVC. They provide a very wide range of properties from soft/elastomeric too hard. They have inherent oxygen and ozone resistance, resist plasticizers, volatility, weathering, and compared to PEs have improved resistance to chemical extraction. Products do not fog at high temperatures as do PVCs and can be made flame retardant. 

J.N. Schramm and R.R. Blanchard, The use of CPE [chlorinated polyethylene] as a compa-tibilizer for reclamation of waste plastic materials, presented at Palisades Section, SPE RETEC, Plastics and Ecology, Cherry Hill Inn, Cherry Hill, NJ, 1970. 

A few plastics which tend to be naturally brittle require an improvement in both their drop (impact) strength and their top loading (compression) strength. In the case of polystyrene, rubber is widely used as an impact modifier. Rigid PVC, particularly when used as a container, may suffer weakness when subjected to, say, a 3 4 foot drop test. Up to 15% of methyl methacrylate butadiene styrene (MBS) copolymer is usually added to improve impact strength. Chlorinated polyethylene has more recently been introduced as a PVC impact modifier. Vinyl acetate is frequently used as a modifier for PVC film. Polythene, LDPE-HOPE can have resistance to stress (environmental stress cracking), improved by the use either of rubber or polyisobutylene. These modifications have not as yet had any pharmaceutical applications. 

These materials may be regarded as low melt viscosity, compatible solid plasticizers. Examples are acrylic copolymers, acrylonitrile butadiene resins, and chlorinated polyethylene. By... 

U.S. Pat. No. 4,250,064 [33] describes usage, along with low-density organic fibers (snch as polyester fiber or cellnlosic fiber), of a combination of coarse and fine inorganic filler snch as calcinm carbonate (20-50% by weight), which makes the organic filler more easily and nniformly dispersed in a plastic matrix (preferably chlorinated polyethylene or a vinyl chloride/vinyl acetate copolymer), avoiding visible clumps of fiber. 

U.S. Pat. No. 6,617,376 [91] (Crane Plastics Co., TimberTech) discloses a cellulosic composite comprising about 20% to about 55% by weight of a cellulosic material, 45-80% by weight of chlorinated polyethylene, and melt-processing rubbers. 

Chlorine occurs in plastics such as PVC, chlorinated polyethylene, and rubber hydrochloride. Some plasticizers also contain chlorine. Flame-proofing agents often contain chlorine or bromine. 

Antitack rubber suitable for manufacturing pneumatic tires is produced from combination of CSP and natural rabber. This composition used 3 wt% of an undisclosed plasticizer (process oil). A paper transport belt made from a blend of CSP and EPDM rabber used 3 phr of polyethylene glycol and 25 phr of dioctyl sebacate. A membrane obtained from blending CSP and chlorinated polyethylene contained 6 phr of tri-(2-etltylhexyl) phosphate. ... 

Chlorinated polyethylene requires larger additions of plasticizers. Amounts of plasticizers and types used in chlorinated polyethylene are very similar to plasticizers used in polyvinylchloride. 

Chlorinated elastomers (polychloroprene, sulphochlorinated polyethylene, chlorinated polyethylene) have fairly good flammability characteristics. Further improvement can be achieved with alumina trihydrate or antimony trioxide. Halogenated phosphoric esters may be applied as plasticizers. 

The recent proliferation of metallocene-based polyolefins and polyolefin elastomers have gained their popularity owing to their density, cost, and ease of processabUity. PVC/POE blends have therefore been investigated as flexible PVC compounds. However, these blends are thermodynamically immiscible and needed suitable compatibiUzers such as the chlorinated polyethylenes (Eastman and Dadmun 2002). Since they are not miscible, POEs do not lower the PVC modulus sufficiently unless some plasticizer or a compatible elastomer such as EPE is also added. Commercially, some PVC/POE alloys are offered by TeknorApex under Flexalloy trade name with a shore A hardness 40-60 and brittle points down to —50 °C. They are claimed to have excellent low-temperature toughness, flexibility, compression set-resistance, and oil resistance. Suitable applications include automotive hoses, seals, gaskets, wire jacketing, etc. 

DuPont Dow Elastomers has evaluated chlorinated polyethylene as a compatibiliser for PVC-based wood plastics composites. 

Plastomer modification of PP continues to progress. Current work in many development laboratories focuses on modification of reactor TPOs to make soft flexible compounds for extruded or calendared sheet. In many such applications flexible PP sheets would replace plasticized polyvinyl chloride (PVC) or PVC blends, chlorinated polyethylene, or EPDM. 

When chlorinated polyether is used instead of butadiene, a copolymer called acrylonitrile-chlorinated polyethylene styrene (ACS) is produced. This copolymer has improved flame resistance and weatherability. [See also acrylonitrile-chlorinated styrene (ACS) teropolymer polyethylene styrene (ACS) terpolymer.] Acrylic styrene acrylonitrile (ASA) is produced by grafting an acrylic ester elastomer onto the styreneacrylonitrile segment. This results in better outdoor weathering. ASA is used in products such as gutters, mailboxes, shutters, and outdoor furniture. (See also acrylic styrene acrylonitrile.) Modifications are also available that enhance adhesion of electroplated coating to the ABS plastic. ABS is the most widely used material for electroplated plastic parts. 

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