Nylon-66 chemical formula: C36H66N6O6X2.
Polyhexamethylene adipamide, commonly known as nylon-66, is a thermoplastic resin generally produced by the condensation polymerization of adipic acid and hexamethylene diamine. Insoluble in general solvents, only soluble in m-cresol, etc. The mechanical strength and hardness are very high, and the rigidity is great. It can be used as engineering plastics, mechanical accessories such as gears, lubricated bearings, instead of non-ferrous metal materials to make machine casings, automobile engine blades, etc., and can also be used to make synthetic fibers.
Overview
A type of thermoplastic resin containing an amide group (—CONH—) in the repeating structural unit of the molecular backbone.
Often made into cylindrical pellets, the molecular weight of polyamide used for plastics is generally 15,000 to 20,000. The common features of various polyamides are flame resistance, high tensile strength (up to 104kPa), wear resistance, good electrical insulation, heat resistance (the heat deformation temperature is above 150℃ at 455kPa), and melting point of 150~250 ℃, the molten resin has high fluidity and a relative density of 1.05 to 1.15 (can be increased to 1.6 by adding fillers). Most of them are non-toxic.
However, when the monomer content in the resin is too high, it is not suitable for long-term contact with skin or food. Countries often have food hygiene regulations on this.
Nylon products
The earliest industrially produced polyamide variety was polyamide 66 (nylon 66). The American DuPont Company W.H. Carothers published the first patent in 1937 , polyamide fiber (nylon yarn) samples were obtained, a pilot plant was established in 1938, and the industrial production equipment was put into operation in 1939. At that time polyamide was mainly used in the production of fibers, ropes and covering materials.
The military application of these materials was greatly developed during World War II, and films and plastics were produced after the war. In 1941, polyamide 6 was put into production in Germany, and polyamide 610 was subsequently developed. In 1950, France developed polyamide 11. In 1958, China successfully trial-produced polyamide 1010, and the Soviet Union successfully trial-produced polyamide. In 1966, polyamide 12 was mass-produced at the Hess Chemical Company in the Federal Republic of Germany.
In 1972, the American DuPont Company realized the industrial production of aromatic polyamide. After the 1970s, the modification of polyamide aroused great interest, especially the development of petrochemical industry. The raw material route of polyamide turned to petroleum. The cost decreased year by year and the output increased year by year, making polyamide develop into a class with many varieties and capable of Polymer materials suitable for various uses.