Resin usually refers to organic polymers that have a range of softening or melting when heated, a tendency to flow under external force when softened, and are solid, semi-solid, or sometimes liquid at room temperature. Broadly speaking, any polymer that can be used as a raw material for processing plastic products is called a resin. There are natural resins and synthetic resins. Natural resins are amorphous organic substances obtained from the secretions of plants and animals in nature, such as rosin, amber, wormwood, and so on. Synthetic resin refers to the resin products obtained by chemical synthesis of simple organic substances or by chemical reaction of certain natural products. Natural resins can be categorized according to the resin components and the history of resin formation. According to the basic components of the resin can be divided into three major categories: ① pure resin, that is, by the terpenes and crude essential oils composed of resin-like substances. Generally insoluble in water, but soluble in organic solvents, such as rosin. ② gum resin or gum resin, is composed of polysaccharide substances, soluble in water or water soluble, but insoluble in alcohol and organic solvents, such as frankincense. ③Oil-containing resin or known as gum, is a resin that contains more essential oils and can be dissolved in oil. According to the formation history of resin can be divided into fossil resin, semi-fossil resin and fresh resin. The latter is the most important source of natural resins. Some natural resins are named by the name of the port where they were first collected and exported, such as ? Ma Resin, Koba Resin, etc.

Synthetic resins are viscous liquids or heat-softened solids, usually have a melting or softening temperature range when heated, in the external force can be plastic flow state, some properties and natural resins are similar. The most important application of synthetic resins is the manufacture of plastics. In order to facilitate processing and improve performance, often add additives, sometimes also used directly for processing and molding, it is often synonymous with plastic. Synthetic resins or the manufacture of synthetic fibers, coatings, adhesives, insulation materials and other basic raw materials. There are many types of synthetic resins. According to the structure of the main chain carbon chain, heterochain and non-carbon chain synthetic resins; according to the characteristics of the synthetic reaction polymerization and polycondensation synthetic resins. In practical application, often according to its thermal behavior is divided into thermoplastic resin and thermosetting resin. The production of synthetic resins from a variety of sources of raw materials, the early coal tar products and calcium carbide acetylene-based, now more oil and natural gas-based products, such as ethylene, propylene, benzene, formaldehyde and urea. Synthetic resin production methods using the body polymerization, suspension polymerization, emulsion polymerization, solution polymerization, melt polymerization and interface polycondensation.

Plastic (Plastics): plastic behavior of the material, the so-called plasticity refers to the role of external forces, deformation occurs, after the cancellation of the external forces, can still maintain the state of the force. Plastic modulus of elasticity between rubber and fiber, the force can be deformed. Soft plastics close to rubber, hard plastics close to fiber.

Plastic refers to the resin (or in the process with monomer direct polymerization) as the main component, to plasticizers, fillers, lubricants, colorants and other additives as auxiliary components, in the process of flow molding materials. Plastics are synthetic polymer compounds that can be freely changed in form and style. Plastic is the use of monomer raw materials to synthesize or condensation reaction polymerization of materials, by synthetic resins and fillers, plasticizers, stabilizers, lubricants, colorants and other additives.