Abstract: The present invention relates to solid particles which comprise at least one lactam, and also at least one activator, and at least one catalyst, to a process for the production of these, and also to the use of these for the production of polyamide, and to a process for the production of polyamide.

Abstract: The present disclosure provides a method for preparing polylactic acid and its products using a twin-screw extruder, comprising the step of mixing carbon dioxide adducts of carbene and lactide, and obtaining polylactic acid and its products via reactive extrusion using a twin-screw extruder.

Abstract: This disclosure provides a method of making polylactic acid using carbon dioxide adducts of carbenes, wherein the adducts of carbenes have a structure represented by formula (I) as follows:

Abstract: A method for preparing nylon microspheres is provided, said method comprising steps (1), (2) and (3) or steps (1?), (2) and (3) as follows: (1) a radically polymerizable monomer is dispersed in a molten lactam monomer, and a free radical initiator is added, so that radical polymerization of the radically polymerizable monomer is carried out, to give a mixture of a free radical polymer and the lactam monomer; or (1?) a mixture of a free radical polymer and a molten lactam monomer is provided; and (2) an initiator and an activator, used for anionic ring-opening polymerization of the lactam monomer, are added to the mixture obtained in step (1) wherein the remaining radically polymerizable monomer and water are removed, or to the mixture obtained in step (1?), so that the anionic ring-opening polymerization of the lactam is carried out to give a polymer alloy of the free radical polymer/polyamide; and (3) the free radical polymer in the polymer alloy obtained in step (2) is removed by dissolution, giving nylon m

Abstract: The invention relates to a liquid initiator for carrying out anionic lactam polymerization. The liquid initiator contains a conversion product of isocyanate (1) with a protic compound (P) and a base (B) in an aprotic solvation agent (S).

Abstract: A process for removing low molecular weight constituents from polyamide 6 or from copolyamides based on caprolactam (herein (co)polyamide) is disclosed. The process comprise subjecting the (co)polyamide to liquid-extraction at a temperature which is above the boiling point of the liquid at atmospheric pressure said liquid containing water in an amount of at least 80 percent relative to its weight.

Abstract: The invention provides a poly(imide-benzoxazole) (PIBO) copolymer prepared from a trimellitic anhydride halide monomer and a bis(o-diaminophenol) monomer. The PIBO copolymer is characterized by the following recurring unit: wherein X is —O—, —S—, —C(CF3)2—, —C(CH3)2—, —CO—, —CH2—, —SO2—, —SO—, or deleted; and n is an integer. The PIBO copolymers of this invention are particularly useful as dielectric layers in semiconductor devices because they possess hydroxyl groups which create better adhesion to semiconductor substrates.

Abstract: A polyamide and a process for preparing the polyamide are disclosed.

Abstract: Provided is a high heat-resistant polymeric fluorescent substance having a divalent condensed polycyclic aromatic group of specific size having a bonding part at specific position shows fluorescence at a long wave length from orange to red, which is useful for fabricating an organic EL device having excellent properties by a coating method.

Abstract: An aliphatic polyester amide which is hydrolysis-resistant includes a ternary polycondensation product of monomeric constituents composed of a monomeric constituent A which is at least one diol having a general formula: HO—R1—OH, where R1 is an aliphatic residue having 2-16 carbon atoms; a monomeric constituent B which is at least one dicarboxylic acid having a general formula: HOOC—R2—COOH, where R2 is an aliphatic residue having 1-14 carbon atoms; and a monomeric constituent C which is at least one diamine having a general formula: H2N—R3—NH2, where R3 is an aliphatic residue having 2-16 carbon atoms and is present in an amount of up to about 5% by weight based on total weight of the monomeric constituents, wherein polycondensation proceeds in the presence of a catalyst comprised of constituent D, which is a metal-containing catalyst, in combination with constituent E, which is at least one of an organic phosphorus compound and an inorganic phosphorus compound, and wherei

Abstract: A method for the production and use of a catalytically-acting liquid system is offered, which has no or only a small proportion of free lactam, and which is of low viscosity and good storage stability and which directly initiates the anionic lactam polymerization.

Abstract: Polyimide precursor solutions comprise an organic liquid and the reaction product of an aromatic dianhydride and an aromatic diaminobenzoxazole capped, on at least one terminal end, with a bifunctional chain extender. The bifunctional chain extender has one functional group reactive with the amine of the aromatic diaminobenzoxazole or the anhydride of the aromatic dianhydride and another functional group which does not form amic acid linkages, but which is capable of further reaction to increase the molecular weight of the polyimide precursor under conditions other than those used to react the aromatic diamine and aromatic dianhydride to form the polyimide precursor. These polyimide precursors can be converted into polyimidebenzoxazole polymers.

Abstract: The morphology of multidimensional, thermally stable oligomers is combined with the inclusion of charge carrier linkages within the polymer arms to produce thermally stable advanced composites from cured oligomers that are conductive or semiconductive if suitably doped.

Abstract: New photosensitive polyamic acid precursors are disclosed which have the formula: ##STR1## where Z is a tetravalent organic radical which contains at least one aromatic ring, Z' is a divalent organic radical which contains at least one aromatic ring, and R* is a photo polymerizable group. Particularly preferred compounds include BPDA-PDA and BPDA-ODA polyamic acid precursors. The precursor compositions within the practice of this invention are i-line, g-line, and i-/g-line active and show good photoresolution. The films formed exhibit excellent self-adhesion and adhesion to glass ceramic and silicon wafer substrates have low internal stress, a very low degree of solvent swelling, high thermal stability, and excellent mechanical properties such as high modulus/tensile strength and high elongation at break.

Abstract: Disclosed are cosmetic melanins of different colors produced by procedures involving oxidative polymerization of monomeric precursors of melanin and/or co-monomers that enhance substantivity or adherence of the melanins to the skin and hair. Also disclosed are methods for preparing cosmetic melanins and methods for using these compositions topically to produce a natural-appearing tan and to prevent damage to skin caused by UV exposure.

Abstract: Polyimide precursor solutions comprise an organic liquid and the reaction product of an aromatic dianhydride and an aromatic diaminobenzoxazole capped, on at least one terminal end, with a bifunctional chain extender. The bifunctional chain extender has one functional group reactive with the amine of the aromatic diaminobenzoxazole or the anhydride of the aromatic dianhydride and another functional group which does not form amic acid linkages, but which is capable of further reaction to increase the molecular weight of the polyimide precursor under conditions other than those used to react the aromatic diamine and aromatic dianhydride to form the polyimide precursor. These polyimide precursors can be converted into polyimidebenzoxazole polymers.

Abstract: A method of preparing a lass of PPV derivatives includes preparing a soluble precursor of a PPV derivative and converting the soluble precursor to a PPV derivative. The converting includes performing either a thermal treatment in a range of temperatures from approximately 25.degree. C. to 400.degree. C. at a reduced pressure or an acid-catalyzed ultraviolet radiation treatment.

Abstract: The thermoplastic molding compositions contain as essential componentsA) from 96 to 99.9% by weight of at least one polyamide,B) from 0.1 to 4% by weight of one or more dialkyl ketones of the general formula I ##STR1## where R and R' are each alkyl of from 10 to 30 carbon atoms, and also, based on the sum total of A) and B),C) from 0 to 40% by weight of an impact modifying rubber,D) from 0 to 60% by weight of fibrous or particulate fillers or a mixture thereof, andE) from 0 to 120% by weight of a modified polyphenylene ether.

Abstract: Polyimide precursor compositions incorporating at least one compound of fula (1), at least one compound of formula (2), at least one compound of formula (3) and at least one compound of formula (4) ##STR1## in which one of the groups R.sup.3 and R.sup.4 represents a hydrogen atom and the other, in the same way as the groups R.sup.1 and R.sup.2, which can be the same or different, in each case represent a hydrocarbon group having 1 to 16 carbon atoms, m is a number between 5 and 20, n is an integer between 1 and 5 and R.sup.5 represents a hydrogen atom, a halogen atom, a hydrocarbon group with 1 to 16 carbon atoms, or a group of formula R.sup.6 --O-- in which R.sup.6 represents a hydrocarbon group having 1 to 16 carbon atoms. The preferred composition contains 30 to 70% by weight of dry matter of compounds of formulas (1), (2) and (3), in which the groups R.sup.1, R.sup.2 and one of the groups R.sup.3 and R.sup.4 is a methyl or ethyl group and the compound of formula (4) is benzyl alcohol.

Abstract: Imide prepolymer compositions containing an unsaturated component (A) and diamine component (B) at the (A)/(B) molar ratio of 0.9-1.5 and 0.01-5.0% by weight, based on the sum of said components (A) and (B), of at least one radical polymerization inhibitors, and preferably further 0.01-5.0% by weight, based on the sum of said components (A) and (B), of at least one compound selected from the group of carboxylic acid and carboxylic acid anhydride.The imide prepolymer compositions of the present invention which contain the above-defined components in specific proportions are tough and excellent in adhesive strength to glass cloths and metals and in heat resistance.

Abstract: There is provided the process for producing an imide-based prepolymer having high solvent solubility by reacting an unsaturated bisimide of formula (I): ##STR1## wherein D is a divalent group having a carbon-to-carbon double bond, and A is a divalent group having at least two carbon atoms, with a diamine in the presence of a radical scavenger.

Abstract: An improved process for the anionic polymerization of lactams is described. Particular azetidinedione compounds are employed as promoters and their use not only permits low polymerization temperatures but gives rise to faster polymerization reactions than prior art procedures allow.The rapid polymerization of caprolactam in accordance with the present invention makes the process particularly suited to RIM procedures for preparing molded polyamides.

Abstract: Polyamides such as nylon-6 type polyamides are prepared by the reaction or copolymerization of a major amount by weight of a lactam and a minor amount by weight of a graft copolymer of maleic anhydride on a low molecular weight liquid conjugated diene polymer or copolymer or of a copolymer of a conjugated diene and a monovinyl aryl monomer or a nitrile. For example, a graft of maleic anhydride on liquid butadiene/acrylonitrile copolymer is copolymerized with epsilon-caprolactam using an anionic lactam polymerization catalyst (a lactamate salt) like the reaction product of ethyl magnesium bromide and epsilon-caprolactam. The present invention may be useful in a RIM (Reaction Injection Molding) process. The resulting polyamides have improved impact strength and water resistance. They can be used to make automobile and truck bodies and parts.

Abstract: The disclosure is concerned with a maleimide-diamine resin composition which is well soluble to a low boiling point solvent and is excellent in heat resistance. The composition is featured by containing a maleimide-diamine adduct having the general formula: ##STR1## wherein A is a mono-, di-, tri- or tetravalent organic group containing at least two carbon atoms, R.sub.1 through R.sub.6 are hydrogen atom, a lower alkyl group, a lower alkoxy group, chlorine atom, bromine atom, trifluoromethyl group, or trichloromethyl group, and m is an integer of 0-4.