Poly chloroprenes vulcanization

Resistance to weathering. Zinc oxide and magnesium oxide stabilize poly-chloroprene against dehydrochlorination. Further, zinc oxide helps vulcanize the rubber, and magnesium oxide reacts with /-butyl phenolic resin to produce a resinate which improves heat resistance of solvent-borne polychloroprene adhesives. 

Anthony, Caston, and Guth obtained considerably better agreement between the experimental stress-strain curve for natural rubber similarly vulcanized and the theoretical equation over the range a = 1 to 4. KinelP found that the retractive force for vulcanized poly-chloroprene increased linearly with a — l/a up to a = 3.5. 

Table 35-4. Glass Transition Temperatures and Solubility Parameters of Various Vulcanized Elastomers and Their Mixtures. 8, Solubility Parameter Br, Poly (butadiene) CR Poly(chloroprene) NBR, Poly(butadiene-co-acrylonitrile) NR, Natural Rubber ...

Poly(2-chloro-1,3-butadlene) or polychloroprene, (-CH2C(CI)=CHCH2-)n, CAS 9010-98-4, is a polymer widely used in practice, for example in automotive industry for the fabrication of belts, gaskets, electrical cables covering, etc. (mainly in vulcanized form). The older procedure for chloroprene preparation starts with acetylene, which is subject to catalytic dimerization followed by addition of HCI to the vinylacetylene molecule. 

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