Abstract: A hollow molded article having a joining site where two or more split objects are welded by plastic welding and comes into contact with pressurized hydrogen, wherein an average spherulite size in a portion which is 500 ?m deep inside from a surface of the hollow molded article is 20 ?m or less, and a tensile strength of a test piece containing the joining site of the hollow molded article is 80% or more based on a tensile strength of a test piece not containing the joining site of the hollow molded article.

Abstract: The present disclosure relates to a polyimide-based block copolymer and a polyimide-based block copolymer film including the same. The polyimide-based block copolymer according to the present disclosure makes it possible to provide a polyimide-based film having low haze and yellow index value while exhibiting excellent transparency.

Abstract: A polyamide resin with an excellent balance of mechanical characteristics such as breaking strength and breaking elongation in a solid state, a molded body containing said polyamide resin, a laminate provided with a film or a sheet containing said polyamide resin, a medical device provided with the aforementioned molded body and/or the aforementioned laminate, and a production method of the aforementioned polyamide resin are provided. A polyamide resin is used which contains: a linear aliphatic dicarbonyl unit as unit (a); a linear aliphatic diamino unit as unit (b); at least one of a unit (b) and a unit (c), each of a prescribed structure; and a trivalent unit (e).

Abstract: An object of the present invention is to provide a polyamideimide resin for an optical member having both high flexibility and bending resistance, and in particular, a polyamideimide resin for a front plate of an image display apparatus, and an optical member such as a front plate containing the polyamideimide resin.

Abstract: A poly(amide-imide) copolymer composition comprising an imide of a polyamic acid and an ultraviolet stabilizer, and a colorless and transparent poly(amide-imide) film including the composition. The poly(amide-imide) copolymer composition according to the present disclosure makes it possible to provide a poly(amide-imide) film exhibiting excellent scratch resistance, UV shielding property, and UV weather resistance while being colorless and transparent. This film can be suitably used as a cover film of various flexible or foldable devices.

Abstract: A method for printing a three-dimensional part with an additive manufacturing system, which includes providing a part material that compositionally has one or more semi-crystalline polymers and one or more secondary materials that are configured to retard crystallization of the one or more semi-crystalline polymers, where the one or more secondary materials are substantially miscible with the one or more semi-crystalline polymers. The method also includes melting the part material in the additive manufacturing system, forming at least a portion of a layer of the three-dimensional part from the melted part material in a build environment, and maintaining the build environment at an annealing temperature that is between a glass transition temperature of the part material and a cold crystallization temperature of the part material.

Abstract: A polyamide powder for selective absorbing sintering, SAS, or selective inhibition sintering, SIS. The polyamide powder has a solution viscosity to ISO 307 of 1.8 to 2 and a rise in the solution viscosity of 0% to 25% when it is subjected to a temperature 20° C. below its melting temperature under air for 20 hours.

Abstract: The present invention discloses high selectivity copolyimide membranes for gas, vapor, and liquid separations. Gas permeation tests on these copolyimide membranes demonstrated that they not only showed high selectivity for CO2/CH4 separation, but also showed extremely high selectivities for H2/CH4 and He/CH4 separations. These copolyimide membranes can be used for a wide range of gas, vapor, and liquid separations such as separations of CO2/CH4, He/CH4, CO2/N2, olefin/paraffin separations (e.g. propylene/propane separation), H2/CH4, He/CH4, O2/N2, iso/normal paraffins, polar molecules such as H2O, H2S, and NH3 mixtures with CH4, N2, H2. The high selectivity copolyimide membranes have UV cross-linkable sulfonyl functional groups and can be used for the preparation of UV cross-linked high selectivity copolyimide membranes with enhanced selectivities. The invention also includes blend polymer membranes comprising the high selectivity copolyimide and polyethersulfone.

Abstract: The invention relates to a method for producing a composite plastic part (CK). A first fiber material (F1) is impregnated with a polyamide matrix polymer (PAM), thereby obtaining a matrix composition (MZ), onto which a surface composition (OZ) is applied, and a first plastic component (K1) is obtained. In a second step, a second plastic component (K2) is molded on the first plastic component (K1), whereby the composite plastic part (CK) is obtained. The invention further relates to the composite plastic part (CK) which can be obtained using the method according to the invention. The invention additionally relates to the use of polyethyleneimine (PEI) for improving the impregnation of the first fiber material (F1) with the polyamide matrix polymer (PAM).

Abstract: The present invention relates to a polyimide-based solution that can be used to produce an isotropic transparent polyimide-based film with high heat resistance and excellent mechanical properties as well as high transmittance. A coating of the polyimide-based solution on a substrate has a haze of 1% or less after storage at a temperature of 30° C. and a humidity of 70% for 30 minutes.

Abstract: A uniaxially-stretched, high yield extruded capacitor film comprising a miscible polymer blend comprising a polyetherimide and a poly(carbonate-arylate ester), wherein the polyetherimide comprises units derived from polymerization of an aromatic dianhydride with a diamine comprising a m-phenylenediamine, a p-phenylenediamine, or combinations thereof, wherein the polyetherimide is endcapped with a substituted or unsubstituted aromatic primary monoamine, wherein the poly(carbonate-arylate ester) comprises repeating bisphenol carbonate units and repeating arylate ester units, wherein the repeating bisphenol carbonate units and the repeating arylate ester units are different from each other, and wherein the high yield extruded capacitor film comprises equal to or greater than about 90 wt. % of the miscible polymer blend entering an extruder used for manufacturing the capacitor film, based on the total weight of miscible polymer blend prior to entering the extruder.

Abstract: In some aspects, the present disclosure provides a polymer composition which comprises two polymer molecules and a compatibilizing agent. In some embodiments, the polymer composition is useful for the preparation of membranes used in the separation of two or more gases. In some embodiments, the polymer composition comprises a polyimide polymer and a polybenzimidazole polymer which have been compatibilizing with a small molecule or a metal organic framework.

Abstract: To provide a method for improving a rejection rate of an RO membrane, which further improves the stability of removal performance (rejection rate) and flux stability (sustainability of contamination resistance). In a method for improving a rejection rate of an RO membrane, including a step of allowing an aqueous solution containing a polyphenol to pass through an RO membrane, the method further includes a step of allowing an aqueous solution containing at least one type selected from the group consisting of a modified poly(vinyl alcohol), a high molecular polysaccharide, and a poly(amino acid) to pass through the RO membrane. The method preferably further includes a step of allowing an aqueous solution containing an organic compound having an amino group and having a molecular weight of 1,000 or less to pass through the RO membrane.

Abstract: A consumable material for use in an additive manufacturing system, the consumable filament comprising a polyamide blend of at least one semi-crystalline polyamide, and at least one amorphous polyamide that is substantially miscible with the at least one semi-crystalline polyamide, and a physical geometry configured to be received by the additive manufacturing system for printing a three-dimensional part from the consumable material in a layer-by-layer manner using an additive manufacturing technique. The consumable material is preferably capable of printing three-dimensional parts having good part strengths and ductilities, and low curl.

Abstract: Disclosed herein are anion-conducting polymers that comprise a cationic benzimidazolium and imidazolium moieties. Methods of forming the polymers and membranes comprising the polymers are also provided.

Abstract: A liquid crystal display is provided, including a first insulating substrate; a second insulating substrate facing the first insulating substrate; a pixel electrode disposed on the first insulating substrate; a common electrode disposed on the first insulating substrate or the second insulating substrate; a first alignment layer disposed on the first insulating substrate; a second alignment layer disposed on the second insulating substrate; and a liquid crystal layer disposed between the first insulating substrate and the second insulating substrate, in which at least one of the first alignment layer and the second alignment layer include a main chain and a plurality of side chains which are connected to the main chain, and at least one of the plurality of side chains includes a reactive mesogen including a vertical expression group and at least two photoreactor groups connected to the vertical expression group.

Abstract: Disclosed herein are anion-conducting polymers that comprise a cationic benzimidazolium and imidazolium moieties. Methods of forming the polymers and membranes comprising the polymers are also provided.

Abstract: Polyimides containing a backbone with at least one nanoparticle component and made from oligomers having endcaps that are difunctional or a mix of di- and monofunctionality are provided. The endcaps may be nadic or phenylethynyl. The backbone may be wholly inorganic or made from a mixture of inorganic and organic groups. The oligomers may be created in-situ using standard polymerization of monomeric reactants chemistry using a solvent or may be provided as a pre-imidized compound that may be either a solid or liquid. It is believed that the nanoparticle component of the polymer backbone provides superior thermo-oxidative stability verses unmodified organic backbones. It is further believed that providing difunctional or a mixture of di- and monofunctional endcaps allows for increased crosslinking to provide improved strength and stiffness verses wholly monofunctional endcapped oligomers for polyimides. The nanoparticle is part of the backbone of the polymer and not solely a pendant group.

Abstract: A resin composition for a refrigerant-transporting hose, including: a semi-aromatic polyamide resin (A) as a main component; an aliphatic polyamide resin (B); and an elastomer (C), in which the aliphatic polyamide resin (B) is dispersed in a phase formed of the semi-aromatic polyamide resin (A) and the elastomer (C), which is not crosslinked, is incorporated in the form of particles into the dispersed aliphatic polyamide resin (B). Thus, excellent refrigerant permeation resistance and acid resistance, and at the same time, for example, extrusion processability and flexibility, are obtained.

Abstract: A polyimide blend nanofiber and its use in battery separator are disclosed. The polyimide blend nanofiber is made of two kinds of polyimide precursors by high pressure electrostatic spinning and then high temperature imidization processing, wherein one of the polyimide precursor does not melt under high temperature, and the other is meltable at a temperature of 300-400° C. The polyimide blend nanofiber of present invention has high temperature-resistance, high chemical stability, high porosity, good mechanical strength and good permeability, and can be applied as battery separator.

Abstract: According to an embodiment of the present disclosure, a method of forming a polyimide film on a substrate is disclosed. Such method can be easily controlled and form a polyimide film applicable as an insulation film. While a wafer is heated at a temperature at which a polyimide film is formed, a cycle, in which the wafer is sequentially supplied with a first processing gas, for example, containing a PMDA-based first monomer, and a second processing gas containing a non-aromatic monomer, for example, an HMDA-based second monomer, is performed for a predetermined number of times. When the processing gases are switched, a replacement gas is supplied into a reaction tube so that the monomers are not mixed together under the atmosphere in the reaction tube.

Abstract: The invention concerns fiber, and a process for making same, the fiber comprising a mixture of at least a first polymer and a second polymer, the first polymer having a structure derived from the reaction of one or more amine monomers and a plurality of acid monomers, wherein the one or more amine monomers includes at least 60 mole percent 5(6)-amino-2-(p-aminophenyl)benzimidazole, and the plurality of acid monomers include those having a structure of Cl—CO—Ar1-CO—Cl & Cl—CO—Ar2-CO—Cl wherein Ar1 is an aromatic group having para-oriented linkages and Ar2 is an aromatic group having meta-oriented linkages, and wherein the plurality of acid monomers has at least 50 mole percent of the monomer containing aromatic group Ar2; and the second polymer has a structure derived from the reaction of metaphenylene diamine and isophthaloyl chloride. This fiber has use in heat-resistant protective apparel fabrics and garments.

Abstract: This invention relates to a film comprising a mixture of at least a first polymer and a second polymer; the first polymer derived from the reaction of one or more amine monomers and a plurality of acid monomers, wherein the one or more amine monomers includes at least 60 mole percent 5(6)-amino-2-(p-aminophenyl)benzimidazole, based on the total amount of amine monomers; and the plurality of acid monomers include those having a structure of Cl—CO—Ar1—CO—Cl & Cl—CO—Ar2—CO—Cl wherein Ar1 is an aromatic group having para-oriented linkages and Ar2 is an aromatic group having meta-oriented linkages, and wherein the plurality of acid monomers has at least 50 mole percent of the monomer containing aromatic group Ar2; and the second polymer derived from the reaction of metaphenylene diamine and isophthaloyl chloride.

Abstract: Phase separated blends of polyaryl ether ketones, polyaryl ketones, polyether ketones, polyether ether ketones and mixtures thereof with at least one polysulfone etherimide, wherein the polysulfone etherimide has greater than or equal to 50 mole % of the polymer linkages contain at least one aryl sulfone group are described. Such blends have improved load bearing capability at high temperature. In another aspect a high crystallization temperature, especially at fast cooling rates, is achieved.

Abstract: A composition, containing at least 50% by weight of a polyamide fraction which comprises: a) from 50 to 95 parts by weight of a polyamide having as copolymerized units bis(4-aminocyclohexyl)methane (PACM) and a linear dicarboxylic acid having from 8 to 18 C atoms; and b) from 50 to 5 parts by weight of a linear aliphatic polyamide having an average of from 8 to 12 C atoms in the monomer units, where the sum of the parts by weight of a) and b) is 100 is provided. The composition can be processed to give a moulded article having high transparency, high toughness and high resistance to chemicals, to solvents and to stress cracking.

Abstract: The present invention is for aromatic poly(ether sulfone imide) membranes and methods for making and using these membranes for gas, vapor, and liquid separations. The membranes may be fabricated into any known membrane configuration including a flat sheet or hollow fiber. An embodiment of the present invention is for aromatic poly(ether sulfone imide) polymers, aromatic poly(ether sulfone imide) membranes and UV cross-linked aromatic poly(ether sulfone imide) membranes made from these polymers.

Abstract: Biodegradable saturated and unsaturated polyester amides (PEA)s made from multiamino acid monomers and methods of making biodegradable saturated and unsaturated PEAs.

Abstract: A tube connector made from a polyamide composition, the polyamide composition including at least one first polyamide A having an average number of carbon atoms per nitrogen atom CA and at least one second polyamide B having an average number of carbon atoms per nitrogen atom CB, wherein CA?8.5 and CB?7.5, and wherein CA<CB. The composition may include a third polyamide C having an average number of carbon atoms per nitrogen atom CC, wherein CB?CC.

Abstract: Disclosed are a liquid crystal alignment agent, a liquid crystal alignment film manufactured using the same, and a liquid crystal display including the liquid crystal alignment film. The liquid crystal alignment agent includes a polymer comprising a polyamic acid including a repeating unit represented by Chemical Formula 1, polyimide including a repeating unit represented by Chemical Formula 2, or a combination thereof: wherein Y1 and Y2 are each independently a divalent organic group derived from diamine, wherein the diamine includes photodiamine represented by Chemical Formula 3 and functional diamine represented by Chemical Formula 5: and wherein the other substituents are the same as defined in the detailed description.

Abstract: The invention discloses a method to produce a blended polymer by mixing polyamide 11 and polyamide 6, 10. The method may be utilize melt mixing or may utilize blended solutions. The invention also includes a blended polymer, wherein the blended polymer is produced from polyamide 11 and polyamide 6,10.

Abstract: Filled phase-separated blends of polyaryl ether ketones, polyaryl ketones, polyether ketones, polyether ether ketones and mixtures thereof with at least one polysulfone etherimide, wherein the polysulfone etherimide has greater than or equal to 50 mole % of the polymer linkages contain at least one aryl sulfone group are described. Such filled blends have improved load-bearing capability at high temperature. In another aspect the filled blends have a higher crystallization temperature, especially at fast cooling rates.

Abstract: Composite polyamide fine particles include a polyamide (A1) which has a melting point or a glass transition temperature of over 100° C. and a polymer (A2) which is different from the polyamide (A1). The composite polyamide fine particles have: a dispersion structure in which a plurality of domains each having an average particle diameter of 0.05 to 100 ?m whose main component is the polymer (A2) are dispersed in a polyamide (A1) based matrix; an average particle diameter of 0.1 to 500 ?m; and a sphericity of 80 or more.

Abstract: Provided are a polyamide combination that includes: a first polyamide including a repeating unit represented by Chemical Formula 1, a repeating unit represented by Chemical Formula 2, or a combination thereof; and a second polyamide including a repeating unit represented by Chemical Formula 3, and a film prepared using the polyamide combination.

Abstract: This disclosure relates to a film for a tire inner liner film that may exhibit uniform excellent physical properties over all directions when applied to a tire, and may secure excellent durability and fatigue resistance in a tire manufacturing process or in an automobile running process, a method for manufacturing the film for a tire inner liner, a pneumatic tire using the tire inner liner film, and a method for manufacturing the pneumatic tire using the tire inner liner film.

Abstract: Poly(?-amino acid) which contain: (A) a glutamic acid ?-ester unit represented by formula (I): and (B) one or more kinds of units selected from a glutamic acid ?-ester unit represented by formula (II), an alanine unit, a phenylalanine unit and an N?-benzyloxycarbonyllysine unit, represented by formula (III), and a glutamic acid ?-ester unit represented by formula (IV) can be dissolved in various solvents and are useful for preparing piezoelectric elements which exhibit superior piezoelectricity.

Abstract: The present invention discloses a new type of polyimide membrane with high permeances and high selectivities for gas separations and particularly for CO2/CH4 and H2/CH4 separations. The polyimide membranes have CO2 permeability of 50 Barrers or higher and single-gas selectivity for CO2/CH4 of 15 or higher at 50° C. under 791 kPa for CO2/CH4 separation. The polyimide membranes have UV cross-linkable functional groups and can be used for the preparation of UV cross-linked polyimide membranes having CO2 permeability of 20 Barrers or higher and single-gas selectivity for CO2/CH4 of 35 or higher at 50° C. under 791 kPa for CO2/CH4 separation.

Abstract: A thermoplastic composition comprises a polymer blend. The polymer blend comprises a first polyimide and a second polyimide. The first polyimide has repeating units derived from a first dianhydride and a first diamine. The second polyimide has repeating units derived from a second dianhydride and a second diamine. Either the first dianhydride and the second dianhydride are the same or the first diamine and the second diamine are the same.

Abstract: A polyamide block copolymer that includes a first segment including a repeating unit represented by Chemical Formula 1, a repeating unit represented by Chemical Formula 2, or a combination thereof; and a second segment including a repeating unit represented by Chemical Formula 3. The variables R1 to R15, and n1 to n8 are defined herein.

Abstract: Provide is a molded product showing low water absorption, high chemical resistance, high crystallinity index. A molded product formed from a polyamide resin composition containing 50 to 99 parts by mass of (A) an aliphatic polyamide resin and 50 to 1 parts by mass of (B) a polyamide resin including 70 mol % or more of a diamine structural unit derived from xylylenediamine and 50 mol % or more of a dicarboxylic acid structural unit derived from sebacic acid, provided that the total of (A) and (B) is 100 parts by mass.

Abstract: A nanodevice composition including N-acetyl cysteine linked to a dendrimer, such as a PAMAM dendrimer or a multiarm PEG polymer, is provided. Also provided is a nanodevice for targeted delivery of a compound to a location in need of treatment. The nanodevice includes a PAMAM dendrimer or multiarm PEG polymer, linked to the compound via a disulfide bond. There is provided a nanodevice composition for localizing and delivering therapeutically active agents, the nanodevice includes a PAMAM dendrimer or multiarm PEG polymer and at least one therapeutically active agent attached to the PAMAM dendrimer or multiarm PEG polymer.

Abstract: A powder mixture is described, which is suitable for a layer-wise manufacturing of a three-dimensional object by solidifying a building material in powder form. The powder mixture consists of a mixture of a first polyamide 12 powder and a second polyamide 12 powder, wherein the first polyamide 12 powder is characterized by an increase of its viscosity number determined in accordance with ISO 307 that is less than 10%, when the powder is exposed for 20 hours to a temperature that lies 10° C. below its melting temperature under nitrogen atmosphere, and the second polyamide 12 powder is characterized by an increase of its viscosity number, determined in accordance with ISO 307, by 15% or more, when the powder is exposed for 20 hours to a temperature that lies 10° C. below its melting temperature under nitrogen atmosphere.

Abstract: To provide a biaxially oriented polyamide-based resin film being excellent in laminate strength, pin-hole resistance under a low-temperature environment, impact resistance, and transparency, and which retains satisfactory a good external appearance even after being sterilized in hot water. A biaxially oriented polyamide-based resin film comprising a polyamide resin and 1 to 5% by mass of a polyamide-based block copolymer, wherein the polyamide-based block copolymer comprises a hard part including a residue of cyclic lactam having 4 to 10 carbon atoms, and a soft part including a residue of polyoxypropylene glycol or polyoxytetramethylene glycol having a weight average molecular weight of 500 to 3000, and the content X of the hard part and the content Y and the weight average molecular weight Mw of the soft part satisfy the following formulae (1) and (2): X+Y=100 (parts by mass) ??(1) 478.74×Mw?0.2989?Y?93 (parts by mass) ??(2).

Abstract: A powder mixture is described, which is suitable for a layer-wise manufacturing of a three-dimensional object by solidifying a building material in powder form. The powder mixture consists of a mixture of a first polyamide 12 powder and a second polyamide 12 powder, wherein the first polyamide 12 powder is characterized by an increase of its viscosity number determined in accordance with ISO 307 that is less than 10%, when the powder is exposed for 20 hours to a temperature that lies 10° C. below its melting temperature under nitrogen atmosphere, and the second polyamide 12 powder is characterized by an increase of its viscosity number, determined in accordance with ISO 307, by 15% or more, when the powder is exposed for 20 hours to a temperature that lies 10° C. below its melting temperature under nitrogen atmosphere.

Abstract: Disclosed is a thermoplastic melt-mixed composition including: a) a polyamide resin; b) a poly(amino acid)-polyol compound provided by reacting: b1) one or more amino acids selected from the group consisting of primary amino acids and secondary amino acids and combinations of these; the amino acid having no more than one hydroxyl group; and b2) one or more polyepoxy compound comprising at least two or more epoxy groups; the poly(amino acid)-polyol compound having a range of at least 10 percent conversion of epoxy equivalents of component (b1) up to, but excluding, the gel point of the components b1) and b2) and c) reinforcing agent; and, optionally, d) polymeric toughener; and f) further additives. Processes for making the composition are also disclosed.

Abstract: Disclosed is a biodegradable polymer comprising an optionally substituted aliphatic hydrocarbon group having 5 or more carbon atoms at at least one terminal of the polymer chain, wherein the biodegradable polymer has a weight-average molecular weight of not less than 35,000 when the biodegradable polymer has a 2-pyrrolidone polymer or copolymer as its main chain and stearic acid at the terminal of the polymer chain; a molded article comprising the biodegradable polymer; and a method for controlling biodegradability of a biodegradable polymer, comprising introducing an optionally substituted aliphatic hydrocarbon group into the terminal of the polymer chain of the biodegradable polymer.

Abstract: A polyamide compound containing: from 25 to 50 mol % of a diamine unit, which contains an aromatic diamine unit represented by the following formula (I), in an amount of 50 mol % or more; from 25 to 50 mol % of a dicarboxylic acid unit, which contains a linear aliphatic dicarboxylic acid unit represented by the following formula (II-1) and/or an aromatic dicarboxylic acid unit represented by the following formula (II-2), in an amount in total of 50 mol % or more; and from 0.1 to 50 mol % of a constitutional unit represented by the following formula (III): wherein n represents an integer of from 2 to 18, Ar represents an arylene group, and R represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

Abstract: To provide a polyamic acid ester-containing polyimide precursor composition having a good storage stability, from which a polyimide film having a high imidization degree and excellent adhesion to an inorganic substrate can be obtained. A polyimide precursor composition comprising a polyamic acid ester, a thermal imidization accelerator and a solvent, wherein the thermal imidization accelerator is a compound which has a carboxy group and an amino group or an imino group which is deprotected by heat to show basicity, and which will not accelerate the imidization of the polyamic acid ester before the protecting group leaves, and a polyimide precursor composition containing a silane coupling agent.

Abstract: Disclosed is a process for producing a polyamic acid solution by reacting a diamine component consisting essentially of 20 mol % to 80 mol % of p-phenylenediamine and 80 mol % to 20 mol % of diaminodiphenyl ether with a tetracarboxylic acid component consisting essentially of 10 mol % to 60 mol % of 2,3,3?,4?-biphenyltetracarboxylic dianhydride and 90 mol % to 40 mol % of 3,3?,4,4?-biphenyltetracarboxylic dianhydride in a solvent, comprising: a first step in which a diamine component is reacted with a molar excess of a tetracarboxylic acid component in a solvent containing more than ? mole of water per mole of the tetracarboxylic acid component, whereby preparing a polyamic acid solution; and a second step in which a diamine component, or a diamine component and a tetracarboxylic acid component are added to the polyamic acid solution obtained in the first step so that the molar amount of the diamine component is substantially equal to the molar amount of the tetracarboxylic acid component, and then the dia

Abstract: A film containing a layer formed from a resin composition containing a polyamide compound (A) and a resin (B), wherein the polyamide compound (A) contains from 25 to 50% by mol of a diamine unit, which contains a particular diamine unit, in an amount of 50% by mol or more; from 25 to 50% by mol of a dicarboxylic acid unit, which contains a particular dicarboxylic acid unit, in an amount of 50% by mol or more; and from 0.1 to 50% by mol of a particular constitutional unit.

Abstract: The invention relates to a polymer film made of a polyamide composition comprising at least 80 weight percentage (wt. %) of a semi-crystalline semi-aromatic polyamide with a melting temperature (Tm) of at least 270° C., wherein the wt. % is relative to the total weight of the polymer composition, wherein the polymer film has an average coefficient of thermal expansion in plane in the temperature range of 20° C.-Tg, measured in plane with the method according to ASTM D969-08, of at most 40 ppm/K. The said film can be made from a polyamide moulding composition comprising said polyamide by film casting followed by biaxial stretching. The film has properties suitable for carrier films in flexible printed circuit boards.