摘要:
A sliding material and a heat resistant filament which primarily comprises a liquid crystal polyimide, a liquid crystal polyamide or a liquid crystal polyamide-imide copolymer having at least one recurring structural unit selected from the formula (1) and the formula (2) and is excellent in heat resistance, mechanical characteristics and other fundamental properties of polyimides, and relates to significant improvement of heat-resistance by heat-treating the sliding material, the filament and the molded items. The liquid crystal polyamide-imide copolymer which comprises in a polymer molecule 0.05.about.0.95 mole ratio of the recurring structural units of the formula (1) and 0.95.about.0.05 mole ratio of recurring structural units of the formula (2) has excellent processing ability ##STR1##
摘要:
A fatigue-resistant polyimide resin composition comprising 100 parts by weight of polyimide having from 0.5 (exclusive) to 1.0 (inclusive) mole ratio of recurring structural units represented by the formula (1) and from 0 (inclusive) to 0.5 (exclusive) mole ratio of recurring structural units represented by the formula (2): ##STR1## wherein X is ##STR2## in the formulas (1) and (2), and having an inherent viscosity of 0.45 dl/g or more; and 5.about.65 parts by weight of a carbon fiber, glass fiber, aromatic polyamide fiber and/or potassium titanate fiber, and an injection molded article having a high fatigue resistance.
摘要:
A polyimide resin composition substantially comprising 1 99.9.about.50 parts by weight of polyimide having recurring structural units of the formula ##STR1## and 2 0.1.about.50 parts by weight of a polyimide which improved melt flowability and is prepared by using 1,3-bis(3-aminophenoxy)benzene or 6,6'-bis(3-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-spirobiindane as essential diamine component, or polyether pyridine having recurring structural units of the formula: ##STR2## is disclosed. Further, a polyimide based resin composition comprising the polyimide resin composition or a polyimide copolymer obtained by using the above diamines and a fibrous reinforcement is disclosed. These compositions have remarkably good processability, excellent heat stability and repeated fatigue characteristics.
摘要:
A heat-resistant and thermoplastic polyimide which has low dielectric characteristics and recurring structural units of the following formula: ##STR1## wherein R is a tetravalent radical having from 2 to 27 carbon atoms and selected from the group consisting of an aliphatic radical, alicyclic radical, monoaromatic radical, condensed polyaromatic radical and noncondensed aromatic radical connected each other with a direct bond or a bridge member; aromatic diamines which are useful for the raw material monomers of the polyimide and have following formulas: ##STR2## and a process for preparing the polyimide of the above formula by reacting these aromatic diamines with a tetracarboxylic dianhydride in the presence of an aromatic dicarboxylic anhydride or aromatic monoamine, and successively thermally or chemically imidizing the resultant polyamic acid; are disclosed.
摘要:
A favorably processable polyimide which has recurring structural units represented by the formula (I): ##STR1## wherein R is a tetravalent radical having from 2 to 27 carbon atoms and is selected from the group consisting of an aliphatic radical, alicyclic radical, monoaromatic radical, condensed polyaromatic radical and noncondensed aromatic radical connected to each other with a direct bond or a bridge member, and is blocked at the polymer chain end with aromatic dicarboxylic anhydride represented by the formula (II): ##STR2## wherein X is a divalent radical selected from the group consisting of a monoaromatic radical having from 6 to 27 carbon atoms, condensed polyaromatic radical and noncondensed aromatic radical connected to each other with a direct bond or a bridge member.
摘要翻译:具有由式(I)表示的重复结构单元的有利的可加工聚酰亚胺:(*化学结构*)(I)其中R是具有2至27个碳原子的四价基团,并且选自脂族基团 ,脂环族基团,单芳族基团,缩合多芳族基团和非缩合芳族基团,其与直接键合或桥连构件相互连接,并且在聚合物链端用由式(II)表示的芳族二羧酸酐封闭:(* CHEMICAL 结构*)(II)其中X是选自具有6至27个碳原子的单芳族基团的二价基团,缩合的多芳族基团和未缩合的芳香基团彼此直接连接或桥接成员。
摘要:
This invention relates to a novel thermoplastic and amorphous polyimide which is readily soluble in organic solvent, a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the thermoplastic polyimide and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition, a polyimide-based composite obtained by molding the above soluble and thermoplastic polyimide in combination with a fibrous reinforcement, and a fibrous reinforcement having a surface modified with the above polyimide.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein m and n are individually an integer of 0 or 1, and R is ##STR2## The polyimide of the invention is essentially amorphous, excellent in melt flow stability in the decreased temperature as compared with conventionally known polyimide and has greatly improved processability.The polyimide of the invention obtained by using a novel aromatic diamino compound as a monomer can control various properties such as melt flow ability and solubility in solvents by side chains and not by principal chain of polyimide. Thus, excellent melt flow property and solubility in solvents can be obtained while maintaining high heat resistance and adhesive property which are derived from benzophenone structure of the diamino compound of the the invention.
摘要:
This invention relates to a novel fluorine-containing polyimide or polyimide copolymer being colorless and having transparency and very low dielectric characteristics, and has a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the polyimide or polyimide copolymer and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member, a trifluoromethyl radical is situated at the 3- or the 4-position on a pyridine nucleus, and an imide nitrogen atom is connected at the 3- or the 4-position to an ether bond.The polyimide or polyimide copolymer has excellent heat resistance, outstanding melt-flow stability and greatly improved processability, and also is colorless and has high transparency and very low dielectric coefficient, and can be expected to be used as raw materials for electric.cndot.electronic appliances and optical instruments due to the above characteristics.
摘要:
This invention relates to a novel polyimide or polyimide copolymer having excellent heat resistance and greatly improved processability, and has a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the polyimide or polyimide copolymer and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein L is an oxygen atom, carbonyl, isopropylidene or hexafluoroisopropylidene, and X is ##STR2## and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.The polyimide or polyimide copolymer is outstanding in melt-flow stability, and has greatly improved processability and excellent heat resistance. Consequently, the polyimide or polyimide copolymer can be applied to structural materials, and electic.cndot.electronic appliances.
摘要:
The present invention relates to an amorphous polyimide or a polyimide copolymer having a requisite structural unit consisting of one or more recurring structural units represented by the formula (1): ##STR1## wherein X is a direct bond, oxygen atom or sulfur atom, and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are individually a hydrogen atom or methyl, and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.Polyimide and the polyimide copolymer of the invention has excellent heat resistance, is outstanding in melt-flow stability, has greatly improved processability, and can be applied to structural materials, and electric- electronic appliances.
摘要:
A heat-resistant and thermoplastic polyimide which has low dielectric characteristics and recurring structural units of the following formula ##STR1## wherein R is a tetravalent radical having from 2 to 27 carbon atoms and selected from the group consisting of an aliphatic radical, alicyclic radical, monoaromatic radical, condensed polyaromatic radical and noncondensed aromatic radical connected each other with a direct bond or a bridge member; aromatic diamines which are useful for the raw material monomers of the polyimide and have following formulas: ##STR2## and ##STR3## and a process for preparing the polyimide of the above formula by reacting these aromatic diamines with a tetracarboxylic dianhydride in the presence of an aromatic dicarboxylic anhydride or aromatic monoamine, and successively thermally or chemically imidizing the resultant polyamic acid.