A dual-cure method for forming a solid polymeric structure is provided. An end-capped, imide-terminated prepolymer is combined with at least one photopolymerizable olefinic monomer, at least one photoinitiator, and a diamine, to form a curable resin composition, which, in a first step, is irradiated under conditions effective to polymerize the at least one olefinic monomer, thus forming a scaffold composed of the prepolymer and the polyolefin with the diamine trapped therein. The irradiated composition is then thermally treated at a temperature effective to cause a transimidization reaction to occur between the prepolymer and the diamine, thereby releasing the end caps of the prepolymer and providing the solid polymeric structure. A curable resin composition comprising an end-capped, imide-terminated prepolymer, at least one photopolymerizable olefinic monomer, at least one photoinitiator, and a diamine, is also provided, as are related methods of use.

A method of making a polyetherimide includes forming an intermediate polyetherimide with an anhydride-amine stoichiometry of 2 to 40 mol % and melt mixing the intermediate polyetherimide with a bis(ether anhydride) for greater than 3 minutes at a temperature 50 to 225 C. greater than the glass transition temperature of a final polyetherimide to produce the final polyetherimide.

The invention relates to a process for producing aromatic polyimides, comprising the following steps: (a) preparation of one or more solid salt(s) by reacting one or more aromatic tetracarboxylic acid(s) and one or more diamine(s) according to a mole ratio ranging from 0.95 to 1.05; (b) drying of the solid salt(s), (c) addition, to the dry salt resulting from step (b), of one or more compound(s) (C) comprising one or more group(s) chosen from a carboxylic acid group, an anhydride group, an ester group and an acyl chloride group; (d) solid-state polymerization of said solid salt(s) in the presence of the compound(s) (C).

A fast-response thermoplastic shape-memory polyimide and a preparation method thereof, related to a polyimide and a preparation method thereof. The present invention aims to solve the problem in high-temperature conditions of slow shape recovery poor stability, and poor mechanical properties of a shape-memory polymer prepared by utilizing an existing method. The structural formula of the polyamide of the present invention is as represented by formula (I). The preparation method is: 1. preparation of a diamine solution; 2. preparation of an anhydride-terminated high molecular weight polyamic acid; 3. preparation of a viscous sol-gel; and, 4. preparation of the thermoplastic shape-memory polyimide. The thermoplastic shape-memory polyimide prepared per the present invention is provided with a very fast shape recovery rate and improved shape-memory effect. The present invention is applicable in the field of polyimide preparation.

Polymer resins for the vat photopolymerization of thermoplastics are provided, in particular for the vat photopolymerization of thermoplastics with exception thermal stability and mechanical properties. In some aspects, the polymer resins are prepared by ring opening of an aromatic dianhydride with an alcohol containing an acrylate or methacrylate to produce a photocrosslinkable diacid monomer; conversion of the photocrosslinkable diacid monomer to a photocrosslinkable diacyl chloride; and polymerization of the photocrosslinkable diacyl chloride with an aromatic diamine to produce a photocrosslinkable precursor polymer. Upon crosslinking and drying, a thermal imidization can yield aromatic polyimide polymers with high yield and with micron-scale structural resolution.

A method for modifying a polyimide includes reacting a first polyimide with an amine to produce a second polyimide having an anhydride-amine stoichiometry of 2 to 40 mol % and reacting the second polyimide with a monoanhydride, a bis(anhydride), a bis(ether anhydride) or a tetracarboxylic acid to produce a final polyimide having an anhydride-amine stoichiometry of 1 to 2 mol %.

The present disclosure relates to a polyimide-based block copolymer film. The polyimide-based block copolymer film according to the present disclosure exhibits excellent an ultraviolet shielding property to be suitably used for substrates for displays, protective films for displays, touch panels, and the like.

A poly(imide-amide) copolymer, which is a product of a reaction between a diamine including an amide structural unit-containing oligomer represented by Chemical Formula 1 and a dianhydride represented by Chemical Formula 3:

##STR00001## wherein, groups and variables in Chemical Formulae 1 and 3 are the same as described in the specification.

A method of making a polyetherimide includes melt mixing a composition comprising an aromatic bis(ether anhydride) and a diamine to form a polyetherimide wherein melt mixing occurs at a temperature 50 to 225 C. greater than the glass transition temperature of the polyetherimide and after the composition attains a weight average molecular weight that is greater than or equal to 20% of the weight average molecular weight of the polyetherimide melt mixing occurs at a pressure less than atmospheric pressure.

The present invention provides a polyimide film comprising a polyimide, of which the Int.sub.f value calculated from equation 1 is 3 or greater when the weight reduction rate measured by the thermogravimetric method (TGA) is 5%. The film according to the present invention can exhibit excellent thermal stability even in high-temperature conditions, and thus maintain excellent heat resistance and mechanical characteristics against high-temperature heat added during the display device manufacturing process.

[00001]$\begin{array}{cc}\frac{\mathrm{Ea}}{\mathrm{RT}}+\ln .Math.\left\{\frac{\mathrm{Ea}}{.Math..Math.R}.Math.P\left(X_f\right)\right\}=\ln .Math..Math.t_f& \left[\mathrm{Equation}.Math..Math.1\right]\end{array}$

In equation 1, Ea, R, T, , P(X.sub.f), and t.sub.f are the same as those defined in the detailed description.