Polymer material: A material based on polymer compounds. Polymer materials are materials composed of compounds with relatively high molecular weight, including rubber, plastics, fibers, coatings, adhesives, and polymer based composite materials. Polymers are the form of life. All living organisms can be seen as a collection of polymers. The structure of polymer materials determines their properties, and by controlling and modifying the structure, polymer materials with different characteristics can be obtained.

Polymer materials are divided into rubber, fiber, plastic, polymer adhesive, polymer coating, and polymer based composite materials according to their characteristics.

① Rubber is a type of linear flexible polymer. Its molecular chain has low intermolecular valence force, good flexibility, and can undergo significant deformation under external forces. After removing external forces, it can quickly return to its original state. There are two types: natural rubber and synthetic rubber.

② Fibers are divided into natural fibers and chemical fibers. The former refers to silk, cotton, hemp, wool, etc. The latter is made from natural or synthetic polymers through spinning and post-treatment. Fibers have high secondary valence, low deformability, and high modulus, and are generally crystalline polymers.

③ Plastic is mainly composed of synthetic resins or chemically modified natural polymers, with fillers, plasticizers, and other additives added. Its intermolecular sub valence force, modulus, and deformation are between rubber and fiber. Generally classified into thermosetting plastics and thermoplastic plastics based on the characteristics of synthetic resins; According to their usage, they are divided into general plastics and engineering plastics.

④ Polymer adhesive is an adhesive material mainly composed of synthetic natural polymer compounds. It is divided into two types: natural and synthetic adhesives. Synthetic adhesives are widely used.

⑤ Polymer coatings are mainly made of polymers as film-forming substances, with the addition of solvents and various additives. According to different film-forming substances, it is divided into oil-based coatings, natural resin coatings, and synthetic resin coatings.

⑥ Polymer based composite materials are a type of composite material made by adding various reinforcing materials to polymer compounds as the matrix. It combines the performance characteristics of existing materials and can be designed according to needs. Polymer composite materials are also known as polymer modification, which can be divided into molecular modification and blend modification.

⑦ Functional polymer materials. Functional polymer materials not only possess the general mechanical properties, insulation properties, and thermal properties of polymers, but also have special functions such as material, energy, and information conversion, magnetism, transmission, and storage. Practical applications include polymer information conversion materials, polymer transparent materials, polymer simulated enzymes, biodegradable polymer materials, polymer shape memory materials, and medical and pharmaceutical polymer materials.

Polymers can be classified into the above categories based on their mechanical properties and usage status. However, there is no strict boundary between various types of polymers. The same polymer can be made into plastic or fiber using different synthesis methods and molding processes, such as nylon. And high polymers such as polyurethane have both glassy properties and good elasticity at room temperature, so it is difficult to say whether they are rubber or plastic.