Peptized Rubber

Some Far East rubber traders sell a softened or peptized rubber. A small quantity of a softening agent or peptizer is added to the latex used to make sheet or crepe 

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RSS 2 was mixed with N-234 carbon black without additive or in the presence of quinonedihne, or with a peptizer (dibenzamidodiphenyl disulfide, activated with a metal chelate). In the case of the peptizer, rubber and carbon black were mixed for 30 s before the addition of carbon black. In the case of the quinone diimine, carbon black and QDI were added 15 s after addition of rubber to the mixer. 

Fig. 10. Unaged and aged tensile strength values for vulcanizates prepared from masticated and peptized rubbers.

The compounds containing QDI (red lines) exhibit much lower viscosity than either the control compound (yellow hnes) or the compound containing the peptizer (blue hnes). The increase in the viscosity as high discharge temperatures are reached is attributed to an increase in bound rubber... 

A-l,3-dimethylbutyl-A -phenyl quinone diimine (6QD1) has been introduced as a multifunctional additive for diene rubbers and provides an advantage in mixing characteristics (functions as peptizer and improves scorch safety) as well as improved performance (better antioxidant activity than paraphenylenediamine antidegradants) of the end products [36]. 

Rubber chemicals (accelerator, antioxidant, retarder, peptizer, blowing and vulcanizing agents)... 

Other kinds of rubber chemicals are blowing agents, peptizers, and retarders. The total market for all chemical additives for rubber is over 250 million Ib/yr. 

This depends on the polymer type and increases with higher dry filler loading and reduces with peptizing agents, plasticizers, softeners, reclaimed rubber or resins. 

The fact that plasticization of rubber in the mixing mill is the result of oxidation implies that oxygen is indispensable for the same. Agents which accelerate oxidation thereby effecting plasticization to a desired mooney viscosity level are called peptizing agents. 

Use Peptizer for rubbers, polymer modifier, lubri-cating-oil additive. 

Endor [Du Pont]. TM for a rubber peptizing agent containing activated zinc salt of pentachlo-rothiophenol. (C6Cl5S)2Zn and 80% inert filler. 

Akrochem Peptizer. [Akrochem] Pqxizing agents for rubber processing aid ftvcfaloraprene. 

Anchor. [Pacific Anchor] Epoxy coring agents, accelerators, antioxidruits for rubber, plastics, latex, cements, adhesives, carpet baddngs, footwear, cable insulation, mechanical goods peptizer. 

Proaid. [Akrochem] Processing and dispersing aid, homogenizing agent softener for rubbers, unsaturated polymers peptizing agent for natural and polyiso-prene rubbw. 

Renacit [Miles/Polysar Rubber] Penta-chlorothiophenol prods. peptizing agent for rubber industry. 

Pentachlorthiofenol Renacit 7 RPA 6 USAF B-51. Peptizer for natural rubber, polyisoprene, styrene/butadiene rubber, polybutadiene, NBR, bu l, chloroprene and blends absorbed on clay, used as a peptizing agent facilitating open rnill and internal mixer mastication in rubber industry, Mildly toxic by ingestion severe eye irritant. Akrochem Chem. Co. Bayer AG Polysar. 

Aktiplast [Rhein Chemie] Blend of zinc salts peptizing and dispersing agents for tire comp., molded, extruded, and hard rubber vulcanization accelerator reclaiming agent for soap rubber processing promoter. 

Peptizers are added to rubber at the beginning of mastication (see later) and are used to increase the efficiency of mastication. They act chemically and effectively at temperatures greater than 65°C and hasten the rate of breakdown of rubber chains during mastication. Common peptizers are zinc thiobenzoate, zinc-2-benzamidothiophenate, thio- 8-naphthol, etc. Processing aids other than the peptizer and compounding ingredients (additives) are added after the rubber attains the desired plasticity on mastication. 

Common process aids, besides the peptizer, are pine tar, mineral oil, wax, factice, coumarone-indene resins, petroleum resins, rosin derivatives, and polyterpenes. Their main effect is to make rubber soft and... 

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