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So far, there are more than ten thousand resin species reported, and no less than 1000 have been produced in industrialization. The selection of plastic materials is to choose a suitable variety among many resin varieties. At first, we can choose too many plastic varieties, there is a dazzling feeling. But in fact, not all resin varieties have been used in practice. The choice of plastic materials we refer to is not an endless choice, but in the common resin varieties.

Selection principle of plastic materials:

1、 Adaptability of plastic materials; 1. comparison of properties of various materials; 2. conditions for unsuitable use of plastics; 3. suitable conditions for plastic selection.

2、 The use performance of plastic products 1. the conditions of use of plastic products a. the stress of plastic products; b. Electrical properties of plastic products; c. Dimensional accuracy requirements for plastic products; d. Permeability requirements for plastic products; e. Requirements for transparency of plastic products; f. Appearance requirements for plastic products. 2. the environment of plastic products A. ambient temperature; b. Environmental humidity; c. Contact medium; d. Light, oxygen and radiation of the environment

3、 The processability of plastics 1. processability of plastics; 2. processing cost of plastics; 3. waste materials for plastic processing

4、 The cost of plastic products 1. The price of plastic raw materials; 2. service life of plastic products; 3. maintenance cost of plastic products. 5. Source of plastic raw materials. In the actual selection process, some resins are very close in performance and difficult to distinguish between them.