Chlorosulfonate polyethylene compositions

Xie, H.-Q. and Y.-M. Ma. 2000. Preparation of conductive polyaniline/chlorosulfonated polyethylene composites via in situ emulsion polymerization and study of their properties. / Appl Polym Sci 76 845-850. 

The use of TAG as a curing agent continues to grow for polyolefins and olefin copolymer plastics and mbbers. Examples include polyethylene (109), chlorosulfonated polyethylene (110), polypropylene (111), ethylene—vinyl acetate (112), ethylene—propylene copolymer (113), acrylonitrile copolymers (114), and methylstyrene polymers (115). In ethylene—propylene copolymer mbber compositions. TAG has been used for injection molding of fenders (116). Unsaturated elastomers, such as EPDM, cross link with TAG by hydrogen abstraction and addition to double bonds in the presence of peroxyketal catalysts (117) (see Elastol rs, synthetic). 

Such compositions give good heat resistance and adhesion to unprepared metal. Adhesives based on chlorosulfonated polyethylene have also been modified by an epoxy resin [ 146]. 

Rubber blends with cure rate mismatch is a burning issue for elastomer sandwich products. For example, in a conveyor belt composite structure there is always a combination of two to three special purpose rubbers and, depending on the rubber composition, the curatives are different. Hence, those composite rubber formulations need special processing and formulation to avoid a gross dissimilarity in their cure rate. Recent research in this area indicated that the modification of one or more rubbers with the same cure sites would be a possible solution. Thus, chlorosulfonated polyethylene (CSP) rubber was modified in laboratory scale with 10 wt% of 93% active meta-phenylene bismaleimide (BMI) and 0.5 wt% of dimethyl-di-(/ r/-butyl-peroxy) hexane (catalyst). Mixing was carried out in an oil heated Banbury-type mixer at 150-160°C. The addition of a catalyst was very critical. After 2 min high-shear dispersive melt mix-... 

Various halogenated polymers are used as the polymeric initiator for ATRP, for example, vinyl chloride-vinyl chloroacetate and styrene-p-chloromethylstyrene copolymers, bromi-nated butyl rubber, and chlorosulfonated polyethylene [Bomer and Matyjaszewski, 2002 Coskun and Temuz, 2003], (The vinyl chloride units have much lower reactivity for ATRP compared to the vinyl chloroacetate units because of steric reasons.) The density of grafting is adjusted by varying the copolymer composition. 

During the last decade many new roofing materials were introduced which are applied in the form of weldable membranes, liquid curable materials, self-adhesive products, and torchable materials. These materials are produced from numerous polymers such as, PVC, chlorinated polyethylene, chlorosulfonated polyethylene, EPDM, acrylics, bitumen, polymer-reinforced bitumen and several other materials. It is beyond the scope of this book to analyze compositional changes in these materials. We will provide a brief overview. 

The above criteria were employed to select several commercially supplied Class PS elastomers for laboratory screening by employing selected tests taken from National Bureau of Standards NBSIR 77-1437(j4) and ANSI/ASTM D-3667-78 specifications for "Rubber Seals Used in Flat-Plate Solar Collectors". Four silicone, three EPDM, two fluorocarbon, three epichlorohydrin, one ethylene-acrylic, one polyacrylic, one chlorosulfonated polyethylene, one bromobutyl and two butyl rubbers were studied in these screening tests. These materials are identified in Table I and those compositions which were revealed by their manufacturers are shown in Table II. Undoubtedly some materials which should have been included were omitted however, we hope that this sampling will provide an indication of the applicability of a wide range of materials for use as sealants in thermal solar collectors. 

Liquid natural rubber, SBR, acrylonitrile elastomers, neoprene, and chlorosulfonated polyethylene are also used as sealant compositions. Filled depolymerized natural rubber and SBR latex are readily cured at room temperature by the incorporation of ultraaccelerators. 

Chlorosulfonated polyethylene (Hypalon) has been used as a roofing composition and blends of this polymer and neoprene have been used as sealants. Block copolymers of styrene and butadiene (Kraton) have also been used as sealants.2 ... 

A. Malas, C.K. Das, Effect of graphene oxide on the physical, mechanical and thermo-mechanical properties of neoprene and chlorosulfonated polyethylene vulcanizates. Composites Part B Engineering, ISSN 1359-8368 79 (September 15, 2015) 639-648. http //dx.doi.Org/10.1016/j.compositesb.2015.04.051. 

Specifically, the adhesives described by Briggs and Muschiatti employ chlorosulfonated polyethylene or mixtures of sulfonyl chlorides and chlorinated polymers as the toughening system. The toughener is dissolved in methyl methacrylate and an amine/aldehyde condensation product is used as the curative. These compositions are described as useful with or without the traditional hydroperoxide initiator. Compositions without hydroperoxide are noticeably slower to cure. 

EPDM successfully competes with other rubbers (butyl, chloroprene, and chlorosulfonated polyethylene) and other materials (PVC, bitumen compounds, and composites), offering quite satisfactory ageing/weathering characteristics associated with good/excellent mechanical properties at a rather low cost. Table 29 illustrates such an application. 

Briggs, P. C., Bonding Method Employing Novel Methacrylate Based Adhesive Compositions Chlorinated or Chlorosulfonated Polyethylene as Adhesion Promoter, U.S. Patent No. 4,773,957, 1988. 

Synthetic fibres with ion-exchange properties were obtained from tapes extruded from polystyrene or its mixtures with polyethylene or polypropylene, by chlorosulfonation by chlorosulfonic acid for cross-linking, followed by treatment with aniline. Ion-exchange composite spun fibres have also been synthesized from a thermoplastic polymer and an aromatic vinyl polymer by immersion of the drawn fibres in chlorosulfonic acid at 20 °C, followed by treatment with dichloromethane, methanol and 10% sodium hydroxide, and drying to yield fibres with an ion-exchange capacity of 2.1 mequiv.g" . ... 

Membranes composed of a sulfonated interpolymer of polyethylene and sjdrene-DVB copolymer were prepared by reaction with mixtures of chlorosulfonic acid and dichloroethane of different compositions. It was discovered that the electrical properties of the resultant membranes were related to the degree of sulfonation. See also VK. Shahi, S.K. Thampy and R. Rangarajan React. Funct. Polym., 2000, 46(1), 39 Chem. Abs., 134, 163756 (Chapter 8, Section 6). 

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