Table 1--resin types used in the rubber industry Reactive resins Non-reactive resins Curing resins Reinforcing resins Tackifying resins Phenol-formaldehyde Phenol-formaldehyde Phenol-formaldehyde Resol type Novolak type Novolak type High styrene resins Hydrocarbon resins Methylene donors Terpene derivatives Resorcinol (formaldehyde) Coumarone
indene Polybutadiene Rosin derivatives Styrene-acrylonitrile Tall oil derivatives Polyvinyl chloride resins Phenol-acetylene condensation Table 2--tread formulation used for resin evaluation Reference Reference Resin Components (phr) + oil (phr) (phr) sSBR: 25% styrene, 42% vinyl, 6570.
Some typical active ingredients are ester plasticizers, coumarone
indene resin, epoxy resins, waxes, petrolatum, liquid polymers, antioxidants, peptizers, coagents, process oils, adhesion promoters and more.
While rosin derivatives and coumarone
indene resins were originally used with natural rubber, the picture has changed drastically with the advent of synthetic rubbers, their blends, etc.
5 Natural Rubber 25 FEF or similar 40 Process oil 10 Coumarone
resin 10 Zinc oxide 5
Liquid hydrocarbon resins, such as coumarone
indene resins, are suggested for improving tack of CSM and NBR [refs.