Chlorosulfonated polyethylene properties

Ozonc-rcsjstant elastomers which have no unsaturation are an exceUent choice when their physical properties suit the appHcation, for example, polyacrylates, polysulfides, siHcones, polyesters, and chlorosulfonated polyethylene (38). Such polymers are also used where high ozone concentrations are encountered. Elastomers with pendant, but not backbone, unsaturation are likewise ozone-resistant. Elastomers of this type are the ethylene—propylene—diene (EPDM) mbbers, which possess a weathering resistance that is not dependent on environmentally sensitive stabilizers. Other elastomers, such as butyl mbber (HR) with low double-bond content, are fairly resistant to ozone. As unsaturation increases, ozone resistance decreases. Chloroprene mbber (CR) is also quite ozone-resistant. 

These conclusions are further suppo] ted by expected physical properties of dried film of chlorosulfonated polyethylene from the different types of ... 

Property ECO, CO Epichlrohydrin homopolymer and copolymer Fluorosihcone EPDM Ethylene propylene CSM Chlorosulfonated polyethylene FPM Fluorocarbon elastomers... 

The polymer requires compounding with normal fillers to produce useful compounds. Chlorosulfonated polyethylene (CSM) excels in resistance to attack by oxygen, ozone, corrosive chemicals, and oil, and in addition has very good electrical properties. Electrical stability and resistance to corona and arc are good. The physical properties and abrasion resistance are also good. Light-colored goods made from CSM have excellent color-fastness. Due to the presence of chlorine atoms, this elastomer shows excellent flame resistance. 

Chlorosulfonated polyethylene (Hypalon) 250 Excellent resistance to oxidizing chemicals, ozone, weathering. Relatively good resistance to oils, grease. Poor resistance to aromatic or chlorinated hydrocarbons. Good mechanical properties. 

The chemical name for Hypalon is chlorosulfonated polyethylene and it has excellent resistance to heat, ozone and oxidising chemicals and has good abrasion resistance. It can be compounded for outstanding resistance to oxidising chemicals, such as sodium hypochlorite solutions in sulfuric acid saturated with chlorine and concentrated phosphoric acid. It is one of the few synthetic rubbers that can be mixed in any colour without loss in mechanical properties. 

Protective crack-resistant coatings, based on chlorosulfonated polyethylene (CSPE), are widely known due to their unique crack- and corrosion-resistant properties as compared to other rubbers. These coatings also have high ozone, weather, and wear resistance, as well as excellent mechanical and dielectric characteristics. 

Dimethacrylates form highly cross-linked and, therefore, brittle polymers. To overcome brittleness, manufacturers often blend dimethacrylates with polyurethanes or other polymers such as low-molecular-weight vinyl-terminated butadiene-acrylonitrile copolymers and chlorosulfonated polyethylene. The modified dimethacrylate systems provide tough adhesives with excellent properties. These can be formulated as two-component adhesives, the catalyst component being added just prior to use or applied separately to the surface to be bonded. One-component systems also have been formulated which can be conveniently cured by ultraviolet radiation. 

Chlorosulfonated polyethylene s)mthetic rubber (CSM) is manufactured by DuPont under the trade name H) alon. In many respects it is similar to neoprene, but it does possess some advantages over neoprene in certain types of service. It has better heat and ozone resistance, better electrical properties, better color stability, and better chemical resistance. 

The major polymers with whieh PVC ean be alloyed are aerylonitrile-butadiene eopolymers, aerylonitrile-butadiene-styrene terpolymer, ethylene-vinylacetate copolymers, chlorinated polyethylene, chlorosulfonated polyethylene, thermoplastic polyurethanes, acrylics and methacrylics, and polycaprolactone. Table 18 lists the property enhancements achieved by blending these polymers with PVC. 

Donskoi and co-workers [54] showed that each of the components of a chlorosulfonated polyethylene (CSPE) mix has its own influence on the fireproofing properties and chemical processes that occur. In this case, the thermal properties of the vulcanisates of CSPE were studied, and also the heat flows from the flame on the surface of the specimen. It was established that the thermooxidative breakdown of CSPE and vulcanisates based on it during heating under dynamic conditions, is a multi-stage process. The results of tests involving various fillers and plasticisers made it possible to create rubber-like, high-impact resistant materials. 

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. 

As a consequence, before 1953, the only possible blends were those of LDPE with other polymers than PO or with elastomers (e.g., chlorosulfonated polyethylene rubber, CSR chlorinated butyl mbber, CBR ethylene/propylene/diene copolymers, EPR, EPDM thermoplastic olefinic elastomer TPE, TPO). However, in addition to the original autoclave polymerization, already in 1938, a tubular reactor was introduced and its product had different properties than that from the autoclave. Also varying the reaction condition affected the degree of short- and long-chain branching in LDPE thus, blending different LDPEs offered a way for optimizing the resin to specific applications. 

Good mechanical properties were reported for PP or PE blends with chlorosulfonated polyethylene, 4.5 wt% CSR, and filled with a large amount of CaS04... 

Chlorosulfonated polyethylene is a saturated chlorohydrocarbon rubber produced from CI2, SO2, and a number of polyethylenes, and contains about 20 to 40% chlorine and 1 to 2% sulftir as sulfonyl chloride. Sulfonyl chloride groups are the curing or cross-linking sites.2 CSM properties are largely based on initial polyethylene (PE) and percent chlorine. A free-radical-based PE with 28% chlorine and 1.24% S has a dynamic shear modulus range from 1000 to 300,000 Ib/in (7 MPa to 2.1 GPa). StiflEhess differs for free-radical-based PE and linear PE, with chlorine content at about 30%, CI2 free-radical-based PE stiffness decreases to minimum value, and at about 35%, CI2 content linear PE stiffness decreases to minimum value. When the CI2 content is increased more than 30 and 35%, respectively, the stiffness (modulus) increases.23... 

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. 

Polyethylene. Chlorosulfonated polyethylene is one of a few examples of a class of polymers, which is formed by chemical substitution on the backbone chain of a preformed polymer. In addition, starting from one specific polyethylene, a whole new series of polymers result, whose properties depend on the degree and randomness of chlorine substitution. So, it is not surprising that the properties of the modified polymer also depend, to a large extent, on those of the precursor olefin resin. 

The addition of a block copolymer of 10 phr epoxidized NR into NR/ chlorosulfonated polyethylene blends increased the tensile properties and tear strength of the blended system. The miscibility of the epoxidized NR was enhanced by an in situ grafting reaction of epoxidized NR onto the surface of the chlorosulfonated polyethylene particles. This graft copolymer reduced the interfacial tension between the chlorosulfonated polyethylene particles and the NR matrix, and the epoxidized NR acted as the load transferring agent between the NR and the chlorosulfonated polyethylene."... 

The natural rubber does not generally exhibit all the desired properties for use in the rubber industry. Thus, it is possible to obtain better mechanical and physical properties at a lower cost by blending natural rubber with synthetic rubbers. Normally, natural rubber is deteriorated by ozone and thermal attacks due to its highly unsaturated backbone, and it also shows low oil and chemical resistances due to its non-polarity. However, these properties can be achieved by blending it with low unsaturated ethylene propylene diene monomer rubber, styrene butadiene rubber, carboxylate styrene butadiene rubber, nitrile butadiene rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, and acrylonitrile butadiene rubber. 

Ethylene acrylic mbber is manufactured by M/s Dupont USA under the trade name of Vamac, and is about half ethylene and half methylacrylate. A small amount of cure site monomer in the molecule provides the ability to cross-link chemically. This rubber is the combination of two major chemicals which give its unique balance of properties. For instance, the backbone structure of the polymer molecule is saturated, and so it is inherently resistant to ozone attack. The acrylic segment provides oil resistance, and the ethylene segment yields low temperature performance. The added feature of this mbber is that there is no halogen present to become corroded. There is slightly more tendency to swell than a homopolymer, such as polyacrylate or acrylonitrile mbber, but it is approximately equal to silicone, chloroprene and Hypolan (chlorosulfonated polyethylene) mbbers. 

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