Heat-resistant adhesive formula

Component dosage /g component dosage /g
3-aminophenol 120.0g 1,3,5 trichlorobenzene 91.0g
Granular potassium hydroxide (purity 86%) 75.0g Xylene 50.0ml
1,3 Dimethyl 2 imidazolinone 750.0 ml N,N Dimethylacetamide 81.7 g
Pyromellitic acid dianhydride 10.9g

Preparation The glue is prepared in two steps.

In the first step, the intermediate 1,3 bis(3-aminophenoxy)-chlorobenzene was synthesized: in a flask with a stirrer and a water separator, the aminophenol, potassium hydroxide, and 1,3 dimethyl were added to the flask. Base 2 imidazolinone 500 ml and xylene 50 ml. The temperature was raised while stirring under a nitrogen atmosphere, and the water in the reaction system was removed through a water separator under reflux of xylene, and the amount of distilled water was 20.5 ml. A solution of 250 ml of 1,3-dimethylimidazolidinone (250 ml) and trichlorobenzene was further added over 1 hour, and the mixture was kept at 150-150°C for 5 hours to distill off the xylene in the system. The reaction was further heated to 170-180° C. for 18 hours. After completion of the reaction, the pressure was immediately reduced to 6666-9333 Pa, and 690 ml of 1,3-dimethylimidazolidinone was recovered by distillation. The residue was put into 1.5 L of water with vigorous stirring, and the lower layer appeared as a brown oil, that is, crude 1,3 bis(3-aminophenoxy)chlorobenzene. After a series of refining processes, the obtained oil is stored in a cold place and crystallized.

In the second step, polyimide was synthesized: Intermediate 16.33 and N,N-dimethylacetamide were added to a vessel equipped with a stirrer, a reflux condenser, and a nitrogen inlet tube, and added in portions at room temperature under a nitrogen atmosphere. The pyromellitic dianhydride was stirred for about 20 hours without raising the temperature of the solution. The polymer was coated on a glass plate and heated at 100° C., 200° C., and 300° C. for 1 hour to obtain a yellowish-through polyimide film. It was inserted into two cold-rolled steel plates preheated to 130°C and cemented for 5 min at 300°C and 1.96 MPa pressure.

Formula 2

Ingredients of 2,2 bis(3,4 dicarboxyphenyl)propane dianhydride 0.049 mol

This dianhydride was used instead of pyromellitic dianhydride, and the rest of the components were the same as in Formula 1, and the reaction was carried out to obtain a polymer film.

Source: 21st Century Fine Chemicals Network