Structure of CR

- Nov 01, 2016-

Sulfur modified neoprene also known as universal, or g. Because it syntheses using sulfur and thiuram adjustable, so have multiple disulfide bond in the molecular chain. Rather than sulfur transfer type is also known as w, manufactured with a mercaptan modifier chain does not contain sulfur.

Micro-structure of neoprene depends on the temperature, when temperature is low then the trans-1,4-structure, high molecular structured, high crystallinity, some of the high molecular weight, low content of low molecular weight parts.

Crystallization of CR capacity higher than that of natural rubber and butadiene rubber and butyl rubber. Because of its macromolecular chain containing mainly vanadium is a 1,4-structure, such as gutta-percha, is the crystallization structure of trans-1,4-. Crystallinity for the processing and application of rubber has a significant impact, unvulcanized after long-term storage in General, Crystal would have arisen, the hardness increase. Vulcanized rubber in-5~21℃ can also have crystallized, below 0 ℃ quickly crystallize, warming will melt Crystal reversible. According to different uses, can be synthesized by polymerization conditions to adjust the different ability of rubber. Domestic CR ability is divided into four levels: micro, low, medium, high; outside is divided into five levels: small, small, medium, large, huge. Crystallization of micro-and small-typically chlorine butadiene copolymers with other monomers, sulfur crystals capacity low, non-sulfur transfer ability is moderate. CR2481, CR2482, AC, AD and other high crystallization adhesive.

Neoprene double bond and the chlorine atoms in the structure are not active enough, not chemical reactions. Reactive sulfide and oxide reactive, ozone reactivity than natural rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber. It cannot be Vulcanized with sulfur curing system. Resistance to ageing, ozone ageing unsaturated rubber is much better than the average.

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