Preparation method of hyperbranched polyester modified organic silicon resin and coating comprising resin

[0038] 1) Carboxyl-terminated hyperbranched polyester

[0039] a) Composition:

[0040] Tribasic acid: 1,3,5-benzenetricarboxylic acid 105g (0.5mol); 1,2,4-benzenetricarboxylic acid 105g (0.5mol);

[0041] Diol: 1,4-cyclohexanediol 11.6g (0.1mol); Neopentyl glycol 83.2g (0.8mol); 1,6-hexanediol 11.8g (0.1mol)

[0042] b) synthesis steps:

[0043] Add tribasic acid and dibasic alcohol into a reactor equipped with heating, condensation and nitrogen protection, raise the temperature to 110°C under nitrogen protection, and keep it for 2 hours; heat it to 240°C at a heating rate of 20°C per hour, and keep it at 1.33kPa 4h; finally cooled to room temperature to obtain 185g carboxyl-terminated hyperbranched polyester.

[0044] c) Properties of carboxyl-terminated hyperbranched polyesters

[0045] The weight-average molecular weight of the carboxyl-terminated hyperbranched polyester was detected by gel permeation chromatography, and the result was 3900.

[0046] The acid value was t

[0074] 1) Carboxyl-terminated hyperbranched polyester

[0075] a) Composition:

[0076] Tribasic acid: 294g (1.4mol) of 1,3,5-benzenetricarboxylic acid; 126g (0.6mol) of 1,2,4-benzenetricarboxylic acid;

[0077] Diol: 15.2g (0.2mol) of 1,3-propanediol; 41.6g (0.4mol) of neopentyl glycol; 36g (0.4mol) of 2-methyl-1,3-propanediol;

[0078] b) synthesis steps:

[0079] Add tribasic acid and dibasic alcohol into a reactor equipped with heating, condensation and nitrogen protection, raise the temperature to 110°C under nitrogen protection, and keep it for 2 hours; heat it to 240°C at a heating rate of 20°C per hour, and keep it at 0.66kPa 2h; finally cooled to room temperature to obtain 470g carboxyl-terminated hyperbranched polyester.

[0080] c) Properties of carboxyl-terminated hyperbranched polyesters

[0081] The weight-average molecular weight of the carboxyl-terminated hyperbranched polyester is detected by gel permeation chromatography, and the result is 1990.

[0082] Th

[0105] 1) Carboxyl-terminated hyperbranched polyester

[0106] a) Composition:

[0107] Tribasic acid: 336g (1.6mol) of 1,2,4-benzenetricarboxylic acid;

[0108] Diol: 4.5g (0.05mol) of 1,4-butanediol; 5.9g (0.05mol) of 1,6-hexanediol; 93.6g (0.9mol) of neopentyl glycol

[0109] b) synthesis steps:

[0110] Add tribasic acid and dibasic alcohol into a reactor equipped with heating, condensation and nitrogen protection, raise the temperature to 110°C under nitrogen protection, and keep it for 2 hours; heat it to 240°C at a heating rate of 20°C per hour, and keep it at 0.78kPa 2.5h; finally cooled to room temperature to obtain 404g carboxyl-terminated hyperbranched polyester.

[0111] c) Properties of carboxyl-terminated hyperbranched polyesters

[0112] The weight-average molecular weight of the carboxyl-terminated hyperbranched polyester was detected by gel permeation chromatography, and the result was 2611.

[0113]The acid value was tested according to the method described