| 配方类型： |
RUBBER, PLASTICS, WAXES |
| 配方说明： |
Polyester C |
| 配方组成： |
Phthalic Anhydride/370 g
Ethylene Glycol/171 g
Maleic Anhydride/736 g
Diethylene Glycol/875 g |
| 配制方法： |
Charge the glycols. Start the agitator and introduce a slow stream of inert gas. Heat to about 80'C and add the maleic anhydride, followed by the phthalic anhydride. Fill the trap with xylene and then add an amount of xylene equal to approximately 5% of the total weight of the charge as shown in the formula (2152X0.05=110 g). Increase the temperature to 160'C during the next hour. Adjust the heating so that refluxing is maintained, and water is removed by "azeotropic" distillation and collected in the trap where it can be measured. The exothermic reaction at the beginning of the experiment is less noticeable in a solvent system.
Let the temperature gradually rise to 200'C over the following three hours; 200 to 210'C should take about one hour, and then permit the temperature to reach 215'C. Maintain this temperature until the acid number is less than 50. Take samples during the course of reaction as usual for the determination of acid numbers. The amount of water collected in the xylene trap will also se |
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