Polymers, monomers, chromophoric polymer dots and related methods are provided. Highly fluorescent chromophoric polymer dots with narrow-band emissions are provided. Methods for synthesizing the chromophoric polymers, preparation methods for forming the chromophoric polymer dots, and biological applications using the unique properties of narrow-band emissions are also provided.

Polymers, monomers, chromophoric polymer dots and related methods are provided. Highly fluorescent chromophoric polymer dots with narrow-band emissions are provided. Methods for synthesizing the chromophoric polymers, preparation methods for forming the chromophoric polymer dots, and biological applications using the unique properties of narrow-band emissions are also provided.

The present specification provides a di-polycyclic compound, and a polymer chain consisting of alternating electron donor compounds and electron acceptor compounds, which include the di-polycyclic compound.

The present specification provides a di-polycyclic compound, and a polymer chain consisting of alternating electron donor compounds and electron acceptor compounds, which include the di-polycyclic compound.

Polymers, monomers, chromophoric polymer dots and related methods are provided. Highly fluorescent chromophoric polymer dots with narrow-band emissions are provided. Methods for synthesizing the chromophoric polymers, preparation methods for forming the chromophoric polymer dots, and biological applications using the unique properties of narrow-band emissions are also provided.

Polymers, monomers, chromophoric polymer dots and related methods are provided. Highly fluorescent chromophoric polymer dots with narrow-band emissions are provided. Methods for synthesizing the chromophoric polymers, preparation methods for forming the chromophoric polymer dots, and biological applications using the unique properties of narrow-band emissions are also provided.

This application provides a polyimide fiber and a preparation method thereof. This method comprises first subjecting a dianhydride compound and a diamine compound to a polymerization reaction in a solvent to obtain a polyamic acid solution, wherein said diamine compound comprises a diamine having a structure of Formula 12 or Formula 13, wherein A is S or O; said dianhydride compound comprises one or more of dianhydrides having structures of Formula 14 and Formula 15; and t is 0 or 1; then subjecting said polyamic acid solution to spinning to obtain a polyamic acid fiber; and sequentially subjecting said polyamic acid fiber to imidization and thermal drawing to obtain a polyimide fiber. The polyimide fiber having the above structure has a higher rigidity and can introduce a hydrogen bond to provide an interaction between molecular chains so as to influence the arrangement of the molecular chain in the polymer and the crystallinity, which imparts more excellent mechanical properties to the polyimide fiber. The polyimide fiber obtained has a higher glass transition temperature (Tg) and a better heat resistance.

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This application provides a polyimide fiber and a preparation method thereof. This method comprises first subjecting a dianhydride compound and a diamine compound to a polymerization reaction in a solvent to obtain a polyamic acid solution, wherein said diamine compound comprises a diamine having a structure of Formula 12 or Formula 13, wherein A is S or O; said dianhydride compound comprises one or more of dianhydrides having structures of Formula 14 and Formula 15; and t is 0 or 1; then subjecting said polyamic acid solution to spinning to obtain a polyamic acid fiber; and sequentially subjecting said polyamic acid fiber to imidization and thermal drawing to obtain a polyimide fiber. The polyimide fiber having the above structure has a higher rigidity and can introduce a hydrogen bond to provide an interaction between molecular chains so as to influence the arrangement of the molecular chain in the polymer and the crystallinity, which imparts more excellent mechanical properties to the polyimide fiber. The polyimide fiber obtained has a higher glass transition temperature (Tg) and a better heat resistance.

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A family of new and novel molecules for mechanically superior two-dimensional (2D) polymers is described herein. By combining stiff carbon-containing cyclic polymer nodal units with more compliant linear polymer bridge units in an ordered, 2D repeating molecular structure it is possible to tailor the mechanical properties of 2D polymers and their assemblies to provide high stiffness, strength, and toughness. Furthermore, the inherent dimensionality of 2D polymers and their ability to be stacked into ordered and chemically interactive ensembles gives them inherent benefits in a variety of barrier and structural applications over current stiff and strong linear polymer technologies.

A family of new and novel molecules for mechanically superior two-dimensional (2D) polymers is described herein. By combining stiff carbon-containing cyclic polymer nodal units with more compliant linear polymer bridge units in an ordered, 2D repeating molecular structure it is possible to tailor the mechanical properties of 2D polymers and their assemblies to provide high stiffness, strength, and toughness. Furthermore, the inherent dimensionality of 2D polymers and their ability to be stacked into ordered and chemically interactive ensembles gives them inherent benefits in a variety of barrier and structural applications over current stiff and strong linear polymer technologies.