METHOD OF PRODUCING POLYMER BINDER Russian patent published in 2010 - IPC C08L61/00 

FIELD: chemistry.

SUBSTANCE: method involves condensation of cyclopentadiene and formaldehyde at 30°C in a methanol solvent medium in molar ratio of cyclopentadiene to formaldehyde between 1:1 and 1:3 using 33% potassium hydroxide solution in methanol as a catalyst in amount of 0.2 mol/mol of cyclopentadiene and then drying the product in a vacuum at 100-110°C until constant weight for 2-3 hours. Aprotic donor-acceptor solvent of the dimethylformamide or dimethylsulphoxide type is added to methanol in an amount equal to 4 times the weight of 33% potassium hydroxide solution in methanol at the step for mixing reagents. The binder can be used in making casting moulds for precision casting nonferrous metals primarily.

EFFECT: high degree of binding formaldehyde with cyclopentadiene, high output of the polymer binder.

2 tbl, 12 ex