1 Preparation of amorphous polyester
423.4 parts of neopentyl glycol were added to a thermocouple reactor equipped with a stirrer, a distillation column connected to a water-cooled condenser, a nitrogen inlet, and a temperature regulator. Heat to 130°C under nitrogen stirring, add 719.6 parts of isophthalic acid and 2.5 parts of n-butyltin trioctoate, gradually heat to 230°C, start from 180°C, distill water from the reactor, react at 230°C for 3h to obtain the product The acid value is 34mgKOH/g, the hydroxyl value is 3mgKOH/g, and the viscosity is 2100mpa.s (60°C)
2 Preparation of semi-crystalline polyester
Add 532.1 parts of 1,4-cyclohexanedimethanol, 15.9 parts of trimethylolpropane, 591.3 parts of adipic acid and 2.5 parts of n-butyltin trioctoate to a distillation column equipped with a stirrer connected to a water-cooled condenser , nitrogen inlet and thermocouple reactor connected to the temperature regulator. Heated to 140°C under nitrogen stirring, at this time water began to distill, gradually heated to 220°C.
After the distillation under atmospheric pressure stopped, add 1.0 parts of tributyl phosphite and 1.0 parts of n-butyltin trioctoate, and gradually add a vacuum of 6.67kpa, and react for 5 hours at 220°C. The acid value of the obtained product was 22mgKOH/g, the hydroxyl value was 3mgKOH/g, and the viscosity was 6500mpa.s (220°C).
3 Preparation of acrylic acid copolymer
Add 80 parts of n-butyl acetate to a thermocouple reactor equipped with a stirrer, a distillation column connected to a water-cooled condenser, a nitrogen inlet and a temperature regulator. Heat with constant stirring while purging with nitrogen. At 125°C, a mixture of 0.8 parts of tert-butyl peroxybenzoate in 20 parts of n-butyl acetate was added within 215 minutes. 22 parts of styrene, 24 parts of glycidyl benzyl propionate, and 40 parts of methyl methyl propionate were added 5 minutes after the start, and the total reaction time was 315 minutes. After distilling off n-butyl acetate, the ICI200°C viscosity of the obtained acrylic acid copolymer was 1600 mpa.s.
4 synthesis
Add the above product into curing agent and pigments and fillers for dry mixing, then use a twin-screw extruder to melt and homogenize at 85°C, cool, put it into a Grinder for grinding, and then sieve the powder according to the particle size requirements, and pack it.
