Polyisocyanate composition, polyurethane optical resin

Abstract

The invention discloses a polyisocyanate composition and a polyurethane optical resin prepared by using the composition. The polyisocyanate composition contains the substance A of the following structure, wherein, R 1 , R 2 same or different, R 1 , R 2 They are an aromatic group, aliphatic or alicyclic hydrocarbylene group with 4-15 carbon atoms, respectively. The polyurethane optical resin is prepared by the polymerization reaction of the polyisocyanate composition and the polythiol compound, and the obtained optical resin has the advantages of low occurrence rate of optical deformation and white turbidity, and good optical transparency.

Description

technical field [0001] The invention relates to a polyisocyanate composition and a polyurethane optical resin prepared by using the polyisocyanate composition, and belongs to the field of polyurethane. Background technique [0002] Optical materials are widely used in vehicle window glass, architectural decorative glass, optical fibers, lenses, spectacle lenses and other fields. The traditional optical materials are mainly inorganic glass, which has disadvantages such as high density, poor impact resistance, and difficult dyeing and processing. Optical resin materials have the advantages of low density, high transparency, good impact resistance, easy processing and dyeing, etc. Optical materials such as spectacle lenses made of optical resin are gradually replacing the existing inorganic glass materials. [0003] Polyurethane resin is an important optical resin material, which is generally obtained by the polymerization of a polyisocyanate composition and a polythiol compoun...

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Problems solved by technology

[0004] In the production process of polyurethane resin lenses, optical deformation or cloudy phenomenon is very easy to occur, which affects the optical performance of the final lens and reduces the qualified rate of lens production. Regarding the mechanism and solution of optical deformation or cloudy phenomenon, the industry did a lot of research

[0005] CN102516487B discloses a method for manufacturing polyurethane resin optical materials. By controlling the moisture content of the composition to 10-300ppm, the prepared optical materials do not produce optical deformation or cloudiness. Distillation, nitrogen stripping, etc. are used to reduce the moisture in mercaptans. This scheme adds additional process flow and is less economical

[0006] CN105102496A discloses a composition for optical materials. Polyurethane optical resins are prepared by combining thiols with specified structures and hydroxyl-containing thiols with specified structures and reacting with polyisocyanate, so as to realize the control of optical deformation occurrence rate in the lens production process. Reduced, it did not provide a beneficial improvement to the control of the cloudiness rate during lens manufacturing, and at the same time, this scheme requires the use of a thiol composition with a specified structure, which has great limitations in industrial implementation

After organic carboxylic acid and phosphoric acid complexing agent are complexed with metal elements, it is easy to form insoluble solids, which will affect the optical transparency of the final resin lens

[0008] CN111217975A discloses a method for preparing resins for optical materials, by controlling the production process of xylylene diisocyanate, reducing the reaction intermediates and impurities containing Cl, Br, NH3Cl, CN, ureido groups, carbodiimide groups, etc. content, the optical material resin prepared by polymerizing polythiol compound and xylylene diisocyanate is colorless and transparent. The core point of the scheme is that after the phosgenation conversion rate reaches 80%, dephosgenation is carried out until the phosgene content is less than 0.1ppm, and then the reaction liquid is separated by centrifugation, and the unconverted hydrochloride is returned to continue the phosgenation reaction. The reaction liquid is separated and refined, the process is complicated and the energy consumption is high, and it is difficult to implement in industrial production

[0009] CN111253551A provides a method for preparing polyurethane optical resin. By controlling the separation and purification of isocyanate raw materials and / or controlling the storage of isocyanate raw materials at 10-35°C, the content of isocyanate dimers in the isocyanate is ≤4wt%. It can effectively reduce the occurrence rate of optical deformation of polyurethane optical resin. The disadvantage of this scheme is that the raw material of isocyanate is stored in a relatively harsh temperature range, which is not conducive to the industrial implementation of this scheme.

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