1、 Definition of resin

Resin usually refers to organic polymers that have a softening or melting scale after being heated, and have a tendency to move under external forces during softening. At room temperature, they are solid, semi-solid, and sometimes liquid. Broadly speaking, any polymer that can be used as a processing material for plastic products is called resin.

Resin can be divided into natural resin and constituent resin. Natural resin refers to amorphous organic substances obtained from the secretions of animals and plants in nature, such as rosin, amber, insect glue, etc. Resin composition refers to resin products obtained by chemical composition of simple organic compounds or chemical reactions of certain natural products.

2、 Classification of resins

There are many ways to classify resins. In addition to natural resins and constitutive resins based on their origin, they can also be classified based on constitutive reactions and main chain composition.

1. Classified by resin composition and reaction

According to this method, resins can be divided into polymers and condensates. Additive polymer refers to a polymer produced by addition polymerization reaction, whose chain structure has the same chemical formula as the molecular formula of monomers, such as polyethylene, polystyrene, polytetrafluoroethylene, etc.

Polycondensates refer to polymers produced by condensation polymerization reactions, with chemical formulas of their layout units different from the molecular formulas of monomers, such as phenolic resins, polyester resins, polyamide resins, etc.

2. Classified by the main chain composition of resin molecules

According to this method, resins can be divided into carbon chain polymers, heterocyclic polymers, and elemental organic polymers.

Carbon chain polymer refers to a polymer whose main chain is composed entirely of carbon atoms, such as polyethylene, polystyrene, etc.

Heterocyclic polymer refers to a polymer whose main chain is composed of atoms of two or more elements such as carbon, oxygen, nitrogen, sulfur, etc., such as polyoxymethylene, polyamide, polysulfone, polyether, etc.

Organic polymers are not necessarily rich in carbon atoms on the main chain, but are mainly composed of atoms of elements such as silicon, oxygen, aluminum, titanium, boron, sulfur, phosphorus, etc., such as organosilicon.