C.I.RESINS Synthetic C.I. Resin – COUMARONE INDENE RESIN is synthesized by modification of Rosin by the addition of Allyl group into the chain structure. It is empirically represent as C17H14O. Because of the presence of the double bond in the side chain -> possessed by the Allyl group, makes C.I. resin responsible for having free double bond in polymeric chain structure, thereby gives excellent Green Tack to the Rubber compounds. This double bond is also get cured in the vulcanisation process.
TACKIFYING RESINS
Creating tack in a rubber compound is a surface phenomenon that relies on contact between the surfaces and formation of chemical bonds Addition of all resin tackifiers to rubber compounds improves the ability of the surfaces to make contact Addition of phenolic resins to rubber compounds allows the formation of chemical bonds based on intermolecular forces of attraction Phenolic tackifier resins are most able to form this type of chemical bonds Better tack means product can be used at lower levels - typically added at around 3-5 pphr - optimum level, usually determined empirically Lower levels of tackifier in formulation results in rubber compounds with reduced heat build up
Intended to crosslink unsaturated elastomers Contains methylol or bromo-methyl groups for reactivity Require halogen donor for activation Acts as plasticizer until cure temperatures are reached. Brominated varieties are available for rapid cure and do not require halogen donor.
A Reinforcing resin, which are added to rubber compounds to adjust physical properties of the compound after it has been fully cured,To provide the rubber compound increased Hardness, toughness, stiffness, abrasion resistance, tear resistance
Resins for the CR Adhesives