In an embodiment, a flame retardant composition comprises 60 to 95 wt % of a polycarbonate; a polysiloxane comprising a repeat unit of the formula (7); wherein the composition comprises 0.5 to 2 wt % of the repeat unit of the formula (7) of the polysiloxane; wherein the polysiloxane is free of one or both of a vinyl graft and repeat units derived from a vinyl monomer; 9 to 18 wt % of talc; 5 to 15 wt % of a phosphorus containing flame retardant; 0 to 1 wt % of a phosphite stabilizer; and 0.1 to 2 wt % of an anti-drip agent.

[Problem] To provide a novel polymer, which fills trenches having narrow widths and high aspect ratios and can form a thicker film. [Means for Solution] The block copolymer comprises a linear or cyclic block A having a polysilane skeleton comprising 5 or more silicon and a block B having a polysilazane skeleton comprising 20 or more silicon.

Disclosed is a hydrophilic and oxygen permeable polymer material, including alicyclic isocyanate, a grafted repeating unit with silicon-containing monomer, and a first hydrophilic monomer. The grafted repeating unit has an average molecular weight less than or equal 5,000, and is in an amount of 20-60% based on the total weight of the hydrophilic and oxygen permeable polymer material. The first hydrophilic monomer is in an amount of 1-40% based on the total weight of the hydrophilic and oxygen permeable polymer material. Also disclosed is a method for preparing the hydrophilic and oxygen permeable polymer material.

Disclosed is a hydrophilic and oxygen permeable polymer material, including alicyclic isocyanate, a grafted repeating unit with silicon-containing monomer, and a first hydrophilic monomer. The grafted repeating unit has an average molecular weight less than or equal 5,000, and is in an amount of 20-60% based on the total weight of the hydrophilic and oxygen permeable polymer material. The first hydrophilic monomer is in an amount of 1-40% based on the total weight of the hydrophilic and oxygen permeable polymer material. Also disclosed is a method for preparing the hydrophilic and oxygen permeable polymer material.

Various embodiments are directed to apparatuses and methods involving an elastomer material comprising a flexible polymer backbone with a particular ratio of at least first moieties and second moieties. The first moieties provide a first number of dynamic bonds resulting from interactions between the first moieties and the second moieties provide a second number of dynamic bonds resulting from interactions between the second moieties, the second number of dynamic bonds having a weaker bonding strength than the first number of dynamic bonds. The elastomer material, based on the ratio of the first moieties and second moieties, exhibits autonomous self-healing, a particular toughness, and is stretchable.

Various embodiments are directed to apparatuses and methods involving an elastomer material comprising a flexible polymer backbone with a particular ratio of at least first moieties and second moieties. The first moieties provide a first number of dynamic bonds resulting from interactions between the first moieties and the second moieties provide a second number of dynamic bonds resulting from interactions between the second moieties, the second number of dynamic bonds having a weaker bonding strength than the first number of dynamic bonds. The elastomer material, based on the ratio of the first moieties and second moieties, exhibits autonomous self-healing, a particular toughness, and is stretchable.

A polyamic acid according to one or more embodiments of the present invention contains a structural unit represented by general formula (1) and a structural unit represented by general formula (2). In general formula (1), the plurality of R.sup.1s are each independently a hydrogen atom, a monovalent aliphatic group or an aromatic group. In general formula (2), the plurality of R.sup.2s are each independently an alkyl group having 1-3 carbon atoms or an aryl group having 6-10 carbon atoms. In general formulas (1) and (2), X is a tetravalent organic group. In general formula (2), the plurality of Ys are each independently an alkylene group having 1-3 carbon atoms or an arylene group having 6-10 carbon atoms, and m is an integer of 51-199.

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The present invention relates to a formulation suitable for the preparation of a highly refractive encapsulation material with good barrier properties towards water vapor for an LED, to an encapsulation material for an LED having a high refractive index and good barrier properties towards water vapor which is obtainable from said formulation and to a light emitting device (LED) comprising said encapsulation material. The formulation comprises a polymer comprising a first repeating unit U.sup.1 and a second repeating unit U.sup.2; and a surface-modified nanoparticle, wherein the surface-modified nanoparticle does not contain any zirconium dioxide.

The present invention relates to a formulation suitable for the preparation of a highly refractive encapsulation material with good barrier properties towards water vapor for an LED, to an encapsulation material for an LED having a high refractive index and good barrier properties towards water vapor which is obtainable from said formulation and to a light emitting device (LED) comprising said encapsulation material. The formulation comprises a polymer comprising a first repeating unit U.sup.1 and a second repeating unit U.sup.2; and a surface-modified nanoparticle, wherein the surface-modified nanoparticle does not contain any zirconium dioxide.

Polymers bearing the following structural elements per molecule: (A) an average of at least two alkoxylated (poly)alkylenimine units, said alkylene being selected from C.sub.2-C.sub.10-alkylene and said alkoxylation being selected from ethoxylation, propoxylation, butoxylation and combinations of at least two of the foregoing, (B) at least one polysiloxane unit, and (C) at least one linkage connecting at least two different alkoxylated (poly)alkylenimine units (A) bearing at least one polysiloxane unit (B), each link-age (C) being selected from organic spacers bearing in the range of from 4 to 30 carbon atoms.