Abstract: The present invention discloses a multiblock copolymer with narrow molecular weight distribution and a preparation method therefor. According to the present disclosure, a series of multiblock copolymers with narrow molecular weight distribution are prepared by adopting a reversible addition chain transfer free radical polymerization technology in an emulsion polymerization system by controlling the feeding sequence of monomers. The molecular weight of the series of multiblock copolymers meets theoretical expectations, the content of dead polymers is low, and the mechanical properties are greatly improved compared with the traditional triblock copolymers.

Abstract: The present invention relates to a method for preparing a covalent organic framework (COF) materials—a reversible polycondensation/termination method, the COF materials prepared by the method have high crystallinity, high specific surface area, regular and controllable morphology. The present invention also relates to a method for repairing defects of COF materials—reversible degradation-recombination, the method can eliminate defects of existing COF materials, thereby increasing the crystallinity and specific surface area of COF materials and improving their morphological characteristics.

Abstract: The present invention discloses a multiblock copolymer with narrow molecular weight distribution and a preparation method therefor. According to the present disclosure, a series of multiblock copolymers with narrow molecular weight distribution are prepared by adopting a reversible addition chain transfer free radical polymerization technology in an emulsion polymerization system by controlling the feeding sequence of monomers. The molecular weight of the series of multiblock copolymers meets theoretical expectations, the content of dead polymers is low, and the mechanical properties are greatly improved compared with the traditional triblock copolymers.

Abstract: A highly reflective gain type photovoltaic packaging adhesive film and usage are provided. The packaging adhesive film is composed of an packaging layer and a reflecting layer, wherein the packaging layer has a thickness of 200 to 500 ?m, and is made by mixing a first primary resin, a modified auxiliary, an ultraviolet auxiliary, an anti-thermal oxidation ageing agent and an initiator and melting and coat casting the same at 60° C. to 200° C. to form a film; and the reflecting layer has a thickness of 5 to 200 ?m and is made by mixing a second primary resin, an auxiliary resin, a first filler, a second filler, modified auxiliary, a diluent and an ultraviolet auxiliary, an anti-thermal oxidation ageing agent and an initiator and coating the same on the surface of the packaging layer and curing the same at 30° C. to 150° C.

Abstract: A macromolecular emulsifier with switchable surface activity, and use thereof for preparation of polymer latex is disclosed. By using the macromolecular emulsifier with switchable surface activity as an emulsifier, a reversibly coagulable and re-dispersible polymer latex can be prepared by emulsion polymerization. The polymer latex can achieve the coagulation of latex particles by heating and aerating with nitrogen, air, inert gas and/or adding a small amount of alkali solution; the coagulated latex particles can be restored and re-dispersed into stable latex by aerating with carbon dioxide and/or adding a small amount of acid solution. The coagulation and re-dispersion process is reversible and is easy to control.

Abstract: A macromolecular emulsifier with switchable surface activity, and use thereof for preparation of polymer latex is disclosed. By using the macromolecular emulsifier with switchable surface activity as an emulsifier, a reversibly coagulable and re-dispersible polymer latex can be prepared by emulsion polymerization. The polymer latex can achieve the coagulation of latex particles by heating and aerating with nitrogen, air, inert gas and/or adding a small amount of alkali solution; the coagulated latex particles can be restored and re-dispersed into stable latex by aerating with carbon dioxide and/or adding a small amount of acid solution. The coagulation and re-dispersion process is reversible and is easy to control.