Abstract:
A process for producing a carboxylated compound, which comprises reacting a carbonyl compound with hydrogen peroxide in the presence of an organo-arsenic acid of the formula (1), ##STR1## wherein: R.sup.1 is a C.sub.1 -C.sub.12 alkyl group which may be substituted or an aryl group which may be substituted,R.sup.2 is a hydroxyl group or the same group as that which defines R.sup.1,or alternatively, R.sup.1 and R.sup.2 may bond to each other to form a five-membered or six-membered ring together with As atoms to which these groups are bonded, andthe substituent(s) substituted on the above groups is/are selected from hydroxyl, carboxyl, carbonyl, sulfonyl, sulfonium, an amino group, an ammonium group, an alkyl group, an alkoxyl group and a halogen atom,while a water concentration in a reaction system is maintained at not more than 2% by weight, thereby to form a corresponding carboxylated compound.
Abstract:
A heat-resistant resin composition comprising a melt-kneaded product of:(A) at least one member selected from the group consisting of a polyamideimide resin precursor composed mainly of a recurring unit of the formula (1)-a, ##STR1## wherein R is a divalent aromatic group or aliphatic group, R.sup.1 is a hydrogen atom, an alkyl group or a phenyl group, and Ar is a trivalent aromatic group composed of at least one six-membered ring, and a polyamideimide resin composed mainly of a recurring unit of the formula (1)-b, ##STR2## wherein R, R.sup.1 and Ar are as defined in the above formula (1)-a, (B) a polyphenylene sulfide resin, and(C) an organic isocyanate compound having at least two isocyanate groups in the molecule, the amount of said organic isocyanate compound being 0.5 to 5 parts by weight based on 100 parts by weight of the total amount of the compounds (A) and (B).
Abstract:
A novel sulfur-containing aromatic vinyl compound represented by the following general formula (I) ##STR1## wherein R.sub.1 represents an alkylene group having 1 to 3 carbon atoms and R.sub.2 represents an alkylene group having 2 to 8 carbon atoms, and the two bonds in the benzene ring are meta or para to each other. A curable composition comprising at least one of the said vinyl compounds, an isocyanate compound and a radical polymerization initiator. On heating, the composition gives a crosslinked polymer article useful as lenses.
Abstract:
A polyphenylene ether random copolymer excelling in heat resistance and resistance to solvents, said copolymer being composed of 50-98 mol% of a structural unit of the formula ##STR1## derived from 2,6-dimethyl phenol and 50-2 mol% of a structural unit of the formula ##STR2## derived from 2,3,6-trimethylphenol, each of said structural units being randomly arranged in the polymeric structure, said copolymer having an intrinsic viscosity, as measured in chloroform at 25.degree. C., of at least 0.3 dl/g.
Abstract:
There is provided a resin composition having well balanced moldability, heat resistance and mechanical strength, which comprises (A) all aromatic polyamideimide resin and (B) a Polyester resin, (C) a polyphenylene sulfide resin or (D) a resin capable of forming an anisotropic molten phase, said aromatic polyamideimide resin containing 5 to 95 mol % of a recurring unit of the formula (1) and 5 to 95 mol % of at least one of a recurring unit of the formula (2) and a recurring unit of the formula (3). Said aromatic polyamideimide resin is prepared by conducting a polymerization reaction of an aromatic tricarboxylic acid anhydride and at least any one of all aromatic dicarboxylic acid and an aliphatic dicarboxylic acid with a diisocyanate compound in plural steps in which in the first step the polymerization reaction is conducted in a temperature range of 50.degree. to 110.degree. C. and in the second and subsequent steps the polymerization reaction is conducted in a temperature range of higher than 110.degree. C. but not higher than 200.degree. C. ##STR1## wherein Ar denotes a trivalent aromatic group, Ar.sub.1 denotes a divalent aromatic group, R.sub.1 denotes a divalent aliphatic group, and R denotes a divalent aromatic or aliphatic group.
Abstract:
A resin composition for optics is disclosed, which mainly comprises a graft copolymer comprising a styrene resin and an aromatic polycarbonate each having a specific molecular weight at a specific ratio of molecular weight and weight, said composition having a micro disperse phase of not more than 0.5 .mu.m. The resin composition has a reduced optical strain and an excellent micro disperse phase and is, therefore, suitable for use as optics.
Abstract:
A resin composition comprising (A) 5 to 95 parts by weight of a copolyphenylene ether derived from a mixture of 50 to 98 mole% of a 2,6-dialkylphenol and 2 to 50 mole% of a 2,3,6-trialkylphenol and (B) 5 to 95 parts by weight of a styrene resin. The composition has superior thermal resistance and oxidation stability under heat and satisfactory mechanical properties, and retains these desirable properties after heat-aging. The composition is suitable for preparation of molded articles.
Abstract:
A photosensitive polyimide precursor composed of the structural units (A) represented by the following general formula (I) and the structural units (B) represented by the following general formula (II), in which the ratio of the molar quantity of the structural units (A) to the sum of the molar quantity of the structural units (A) and that of the structural units (B) is 0.01 or greater, and having a viscosity of 100 cP or above as measured at 25.degree. C. in the state of a 10% by weight solution in N-methylpyrrolidone: ##STR1## wherein R.sub.1 represents a tetravalent aromatic hydrocarbon residue; R.sub.2 represents a divalent aromatic hydrocarbon residue; X, identical or different represents a halogen or an alkyl group; and m represents 0 or an integer from 1 to 4. The photosensitivity of the present photosensitive polyimide precursor is about 20 to 100 times that of conventional products. After heat dehydration cyclization, it shows a heat resistance of 400.degree. C. or above.
Abstract:
The photosensitive polyimide precursor of the invention has a recurring unit represented by the following general formula [I]: ##STR1## (R.sub.1 represents a tetravalent aromatic hydrocarbon residue; R.sub.2 and R.sub.3 each represent a divalent aromatic or aliphatic hydrocarbon residue; and R.sub.4 represents a divalent aromatic hydrocarbon residue represented by ##STR2## wherein R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, R.sub.10, R.sub.11 and R.sub.12, identical or different, each represent hydrogen atom, a halogen group or an alkyl group). The photosensitive polyimide precursor of the invention has a viscosity of 50 centipoises or above as measured at 23.degree. C. in the state of a 10% (by weight) solution in N,N-dimethylacetamide. Its photosensitivity is as high as about 20-100 times that of prior products. After heat cyclization, it exhibits a heat resistance of 400.degree. C. or above.The photosensitive polyimide precursor of the invention can be produced by subjecting a tetracarboxylic acid dianhydride and a diamino compound to a polycondensation reaction in an organic polar solvent.
Abstract:
Polyphenylene ethers, self-condensation products of phenols, having desired polymerization degree are prepared by a process which comprises terminating the reaction by adding simultaneously at least one member selected from the class consisting of dioxybenzenes and/or benzoquinones and a reducing agent to the reaction medium at the stage of the desired polymerization degree in the oxidative polycondensation of phenols in the presence of a complex catalyst.