Resoles cold-setting

In cold-set applications, the cost of resorcinol as a commercial commodity has led to its well-known grafting onto phenol-formaldehyde resols to provide... 

ALKALINE PHENOLIC Resol - Alkaline phenol-formaldehyde resin 1. Gas hardened (alkaline phenohc cold- box) 2. Self-setting (alkaline phenohc no bake) Gas hardened with methyl formate vapour - low Cold-set with esters - low Formaldehyde Phenol Methyl formate Formaldehyde Phenol Esters ... 

Resol- ester methyl formate hardened sand Mechanical Mechanical friction, impact, pneumatic chafing With limitations, in mouldmaking with methyl formate sands - regeneration as resol-ester cold setting but with lower yield - embrittlement of binder components ... 

Alkaline phenolic resin, ester hardened. The binder is a low viscosity, highly alkaline phenolic resole resin (1.2 to 1.7%). The hardener is a liquid organic ester (18 to 25%). Sand is mixed with hardener and resin, usually in a continuous mixer. The speed of setting is controlled by the type of ester used. Low sand temperature slows the cure rate, but special hardeners are available for cold and warm sand. In 24 h compression strength can reach 4000 kPa (600 psi). 

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