Resins are made of natural resins and synthetic resins. Natural resin is an amorphous organic matter from the secretions of plants and animals in nature, such as rosin, shellac, amber, etc.. Synthetic resin is a kind of resin product obtained by chemical synthesis of simple organic substance or some natural product, such as phenolic resin and polyvinyl chloride resin, among which synthetic resin is the main component of plastics.The difference between the two is still great. There is no ester in the resin, which is not ester by definition.
Resin: usually refers to the heat after hardening or melting range, softening when there is a tendency to flow under the action of external force, under normal temperature is solid, semi-solid, and sometimes liquid organic polymers. Broadly speaking, any polymer compound that can be used as plastic material for processing raw materials is called resin.
Ester: a class of derivatives of carboxylic acids, compounds produced by the dehydration of carboxylic acids with alcohols (phenols).
