353 results about "Polybutylene terephthalate" patented technology

The invention belongs to the technical field of high polymer materials, and particularly relates to a high-strength papermaking forming net fiber. Comprising the following raw materials in parts by weight: 75-90 parts of polyethylene glycol terephthalate, 5-15 parts of polybutylene terephthalate, 3-10 parts of a modified fiber filler, 2-5 parts of modified graphene, 2-8 parts of silicon dioxide, 0.5-2 parts of a silane coupling agent KH-560, 1-3 parts of an anti-hydrolysis agent, 0.5-1.5 parts of an antioxidant and 0.3-1 part of a lubricant. Wherein the modified fiber filler is prepared by sequentially carrying out modification processes such as silane coupling agent, citric acid-glycerol esterification, iron bismuth oxide loading and the like on glass fibers; the modified graphene is prepared by introducing dopamine, cerium ions and glycidyl methacrylate for modification. The mechanical strength, the hydrolysis resistance and the wear resistance of the fiber are remarkably improved through the synergistic effect of all the components and the melt spinning-multi-stage stretching process, and the fiber is particularly suitable for a forming net of a high-speed paper machine.

The invention belongs to the technical field of copolymerization modification of degradable polyester, and relates to a depolymerization method and application of polybutylene terephthalate. During depolymerization, polybutylene terephthalate, dimethyl carbonate and dihydric alcohol are mixed and then subjected to a depolymerization reaction, and an intermediate ester is prepared; the dihydric alcohol is dihydric alcohol which does not form a ring with dimethyl carbonate in the depolymerization reaction process; the molar weight of the dimethyl carbonate is 10-30% of the molar weight of a repetitive unit of the polybutylene terephthalate; the sum of the molar weight of a 1, 4-butanediol unit in the polybutylene terephthalate and the molar weight of the added dihydric alcohol is a, the sum of the molar weight of a terephthalic acid unit in the polybutylene terephthalate and the molar weight of the added dimethyl carbonate is b, and the ratio of b to a is (1.2-1.5): 1; during application, the prepared intermediate ester is subjected to transesterification under the condition of negative pressure to obtain the copolyester. The depolymerization method is simple and easy to implement; the depolymerization product can be directly applied.

The invention discloses a copper-clad plate material containing elastomer resin and a preparation method of the copper-clad plate material, and belongs to the technical field of new materials. The method comprises the following steps: mixing a styrene-butadiene-styrene block copolymer with polybutadiene rubber, adding nano-montmorillonite, and carrying out intercalation modification through hexadecyl trimethyl ammonium bromide to prepare nano-modified elastomer resin; the preparation method comprises the following steps: mixing polybutylene terephthalate with nano silicon dioxide, and carrying out surface modification by gamma-aminopropyltriethoxysilane and hexamethyldisilazane to obtain a resin matrix; mixing the two phases, adding citric acid, and carrying out microwave heating and high-shear dispersion to obtain a discrete material; carrying out hot pressing on the dispersion, adding polyurethane and polylactic acid, uniformly mixing, adding polydimethylsiloxane and sodium dodecyl benzene sulfonate, and curing to obtain a cured product; and coating the surface of the cured product with a nano-copper layer. The material has the characteristics of high peel strength, low dielectric loss, low water absorption and low thermal expansion, and is suitable for the field of high-speed low-loss copper-clad plates.

The invention discloses a processing method of a polybutylene terephthalate bar with laser etching performance, and relates to the technical field of high polymer material processing and surface modification.The processing method comprises the following steps that in the material melting stage, a synchronous observation system of a melt rheological behavior and a temperature field is established, micro-amplitude sine torque disturbance is introduced, and the temperature field is measured; obtaining dynamic response of viscosity and shear rate, and generating a flowing fingerprint baseline; and performing spectrum decomposition on the flow fingerprint baseline, extracting signal components causing pressure pulsation, determining a critical shear rate threshold and time delay thereof, and forming a discrimination condition of an unstable region. According to the method, shear characteristics are extracted through rheological disturbance and thermal field synchronous observation, space mask driving process simulation is constructed, a feedforward adjusting curve is output, density online estimation and phase recognition are introduced, micro-pulse disturbance and temperature fine adjustment are combined, closed-loop control is formed, melt flow is dynamically stabilized, and laser engraving consistency and the product yield are improved.

The invention discloses a waterproof bag film material and a preparation method thereof, relates to the technical field of polybutylene terephthalate polymer materials, and belongs to the patent classification number C08L67 / 02. The method comprises the following steps: sequentially carrying out silane coupling agent modification and solid-phase free radical polymerization on activated gas-phase nano silicon dioxide to construct a core-shell structure nano reinforced filler with rich epoxy groups on the surface; carrying out melt blending extrusion on the mixture, PBT (Polybutylene Terephthalate) resin, a chain extender, an end-capping reagent and the like to obtain hydrolysis-resistant modified granules; a PBT base film is prepared through casting, two-way stretching and heat setting; the preparation method comprises the following steps: performing ultraviolet ozone activation on a base film, coating a super-hydrophobic coating solution prepared from aminated nano silicon dioxide, epoxy-terminated polydimethylsiloxane, a cross-linking agent and an accelerant, and heating and curing to finally obtain the high-strength high-waterproof PBT waterproof bag film. The prepared film has excellent mechanical strength, body hydrolysis resistance and super-hydrophobic surface, the water contact angle is high, the coating adhesive force is high, and the waterproof performance is lasting and stable under high-frequency bending.

The invention discloses self-adhesive single-component liquid silicone rubber with low compression set and a preparation method thereof. The preparation method comprises the following steps: kneading high-viscosity double-end vinyl polydimethylsiloxane, white carbon black, hexamethyldisilazane and water to prepare base rubber; and uniformly mixing and stirring the base rubber with double-end vinyl polydimethylsiloxane, polydimethylmethylvinylsiloxane, polydimethylmethylhydrosiloxane, a first functional aid, a second functional aid, an inhibitor and a catalyst in proportion to prepare the single-component liquid silicone rubber. The silicone rubber has excellent bonding performance on various substrates such as stainless steel, aluminum materials, copper materials, kovar alloys, nylon, polycarbonate and PBT (polybutylene terephthalate), has excellent mechanical properties and low compression set rate, is suitable for sealing and bonding of various automobile, industrial and electronic components, and has wide application prospects. The present invention relates to a sealing strip, in particular to a sealing adhesive scenario for in-situ curing sealing gasket (CIPG) applications, instead of a conventional sealing strip.

The invention belongs to the field of composite materials, and discloses a high-airtightness nano injection molding polybutylene terephthalate composite material and application thereof. The composite material comprises the following components in percentage by weight: 23%-82.5% of PBT (Polybutylece Terephthalate); 5%-15% of polyarylester; 2%-8% of a reactive flexibilizer; 0.5 to 2% of an ionomer; 0-1% of an antioxidant; 0-1% of a release agent; 10%-50% of glass fiber; the PBT composite material provided by the invention can realize high and stable air tightness, and also has high aluminum alloy binding force and good mechanical properties. Meanwhile, the preparation method disclosed by the invention is simple and feasible, and is suitable for large-scale production.

The invention discloses a hydrolysis-resistant PBT reinforced material capable of being subjected to laser welding and a preparation method of the hydrolysis-resistant PBT reinforced material, and belongs to the field of engineering plastics. Comprising the following raw materials in parts by mass: 45-70 parts of PBT resin, 0.5-1 part of a nucleating agent, 0.5-1 part of a nucleating auxiliary agent, 0.1-1 part of an antioxidant, 0.1-1 part of a lubricant, 0.2-0.8 part of a hydrolysis-resistant agent, 1-3 parts of a toughening agent and 25-45 parts of glass fibers, the nucleating auxiliary agent is sodium-doped potassium aluminosilicate. The nucleating agent can improve the crystallization rate of PBT, refine the grain size and reduce light scattering, and the hydrolysis-resistant agent can block autocatalytic hydrolysis circulation. And the composite sodium-doped potassium aluminosilicate not only can provide a large number of sites for PBT nucleation, but also can adsorb and capture water molecules in the environment and small molecules in an adsorption material and reduce hydrolysis reaction, so that the reinforced PBT material can be suitable for laser welding, and the long-term stability of the material in a high-temperature and humid environment can be guaranteed.

The invention discloses a high specific surface area polyester fiber and a preparation method thereof, polybutylene terephthalate, polyethylene glycol and an antioxidant are put into a twin-screw extruder in proportion to obtain modified polyethylene glycol, the modified polyethylene glycol is used as a sea phase, the modified polyethylene glycol and PET are used as an island phase to carry out melt blending spinning, and after heat setting, drafting is carried out to obtain a sea-island fiber with PET as the island phase. An alkali dissolution-alcohol dissolution synergistic effect system is constructed by utilizing the alkali dissolution characteristic of low-molecular-weight polybutylene terephthalate and the alcohol dissolution characteristic of polyethylene glycol in the marine phase component, under the condition of 50-60 DEG C, an alkali agent directionally breaks ester bonds of polybutylene terephthalate, an alcohol solvent synchronously dissolves polyethylene glycol, efficient marine phase stripping is achieved, and the service life of the marine phase component is prolonged. And finally, the high-specific-surface-area polyester fiber with a complete structure and an excellent specific surface area is prepared.

The invention relates to the field of textile fabrics, and discloses a polylactic acid fabric and a preparation method thereof. The polylactic acid fabric is prepared by weaving polylactic acid fibers, the polylactic acid fibers are prepared by melt spinning of a polylactic acid material body, and the polylactic acid material body is prepared from the following raw materials in parts by weight: 100-120 parts of polylactic acid resin, 12-20 parts of a heat-resistant moisture absorbent, 6-10 parts of a toughening agent and 0.2-0.4 part of an antioxidant; the heat-resistant moisture absorbent is prepared from lignin fibers, poly (ethylene 2, 5-furandicarboxylate), poly (butylene adipate-co-terephthalate) and a dispersing agent. The preparation method comprises the following steps of melt spinning, rib knitting, heat setting, dyeing and aftertreatment. The polylactic acid fabric prepared by the invention has better heat resistance, moisture absorption and shrink deformation resistance, and is suitable for scenes with higher requirements on heat resistance and moisture absorption, such as underwear or infant clothes.

Thermoplastic compositions include: a. from about 1 wt% to about 70 wt% of a polycarbonate homopolymer component; b. from about 10 wt% to about 40 wt% of a polybutylene terephthalate (PBT) component; c. from about 5 wt% to about 30 wt% of a polycarbonate copolymer component; and d. from about 1 wt% to about 15 wt% of a flame retardant component comprising a cyclic phosphazene compound having an oxaphosphorin ring-containing structure. The compositions have improved heat resistance and flame retardant properties.

The present application relates to a fan blade (10) for an industrial axial fan. The fan blade (10) comprises an airfoil (12) and a blade root (14) arranged proximal to the airfoil (12) and configured for attaching the fan blade (10) to a hub (62) of an axial flow fan. The airfoil (12) includes a tip (22) at a distal end (23) and a base (24) at a proximal end (25), a leading edge (26) and an oppositely disposed trailing edge (28), whereby both edges (26, 28) extend from the tip (22) to the base (24). The airfoil (12) has a variable thickness defined as a distance between a top surface (30) and a bottom surface (32). Furthermore, the airfoil (12) is an injection molded unitary structure integrally formed in one piece from a composite material, where the composite material comprises carbon fibers and a thermoplastic selected from the group consisting of polyamide, polybutylene terephthalate and polypropylene.

The utility model belongs to the technical field of optical cables, and particularly discloses a dry type tight tube circular optical cable, which comprises an optical fiber and a tight tube, the tight tube is wrapped outside the optical fiber, water blocking yarn is wrapped outside the tight tube, a PBT (polybutylene terephthalate) sleeve is wrapped outside the water blocking yarn, a blended layer is wrapped outside the PBT sleeve, a shielding layer is wrapped outside the blended layer, and the shielding layer is wrapped outside the shielding layer. And the outer side of the shielding layer is wrapped with a rubber sleeve. According to the dry type tight tube circular optical cable, the tight tube wraps the outer side of the optical fiber, the circular optical cable adopts the blending layer composed of the aramid fiber and the glass fiber yarn as the reinforcing piece, the aramid fiber has excellent mechanical and physical properties and chemical properties and is light in weight, good in insulating property, high in elasticity modulus and high in strength, the aramid fiber evenly wraps the periphery of the optical fiber, and therefore the optical fiber is not prone to falling off. Compared with a common butterfly cable, the optical cable can bear higher tensile force, the tensile performance of the optical cable can be enhanced, and the problem that the structural strength of the optical cable is poor is solved.

The invention discloses a method for preparing an aromatic phosphate salt nucleating agent by using nanoscale aluminum chloride, and belongs to the technical field of polymer nucleating agents. 2, 2-methylene-bis (4, 6-di-tert-butylphenol) and phosphorus oxychloride are used as raw materials, the nanoscale aluminum chloride with the particle size of 20-50nm is selected as an inorganic Lewis acid catalyst and acid binding agent, and the aromatic phosphate salt nucleating agent is prepared by using a one-step method. The preparation method comprises the following steps: replacing the traditional organic acid-binding agents such as triethylamine and pyridine, and synthesizing bis [2, 2 '-methylene bis (4, 6-di-tert-butylphenoxy) phosphate] hydroxyl sodium salt by a one-pot method of condensation, hydrolysis for salt removal and neutralization for salt formation; the purity of the product can reach 99% or above through one-time suction filtration, multiple times of washing are not needed, salt-containing wastewater can be recycled as industrial water after being neutralized, and the environmental protection pressure is greatly reduced; the nucleating agent is suitable for modification processing of polymers such as polypropylene (PP), polyethylene glycol terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA) and the like, and especially meets the strict requirements on the purity and environmental protection property of the nucleating agent in an olefin polymerization process.

Provided are a method for efficiently producing a recycled polybutylene terephthalate resin from a material for recycling that includes polybutylene terephthalate, a method for separating polybutylene terephthalate, and a method for recovering a solution that includes at least polybutylene terephthalate.　This method for producing a recycled polybutylene terephthalate resin from a material for recycling that includes polybutylene terephthalate and a polycarbonate includes step 1, which is a step for placing the material for recycling in a solvent (solvent S1) that has a set swelling rate with regard to polybutylene terephthalate, heating and stirring the result, and separating a solution A and insoluble matter B that includes at least the polybutylene terephthalate.

This polyester resin composition contains a polybutylene terephthalate resin, a recycled polyethylene terephthalate resin, a transesterification inhibitor, a carbodiimide compound, and an elastomer. The amount of terminal hydroxyl groups in the polybutylene terephthalate resin is 30-70 mmol / kg relative to the total amount of the polybutylene terephthalate resin and the recycled polyethylene terephthalate resin. The amount of the carbodiimide compound is 0.2-1.5 mass% relative to the total amount of the polyester resin composition. The amount of the elastomer is 3-15 mass% relative to the total amount of the polyester resin composition.

An optically anisotropic polymer thin film includes a crystallizable polymer and an additive configured to interact with the polymer (e.g., via π-π interactions) to facilitate chain alignment and, in some examples, create a higher crystalline content within the polymer thin film. The polymer thin film may be characterized by a bimodal molecular weight distribution where the molecular weight of the additive may be less than approximately 50% of the molecular weight of the crystallizable polymer. Example crystallizable polymers include polyethylene naphthalate, polyethylene terephthalate, polybutylene naphthalate, polybutylene terephthalate, as well as derivatives thereof. Example additives, which may occupy up to approximately 10 wt. % of the polymer thin film, include aromatic ester oligomers, aromatic amide oligomers, and polycyclic aromatic hydrocarbons, for example. The optically anisotropic polymer thin film may be characterized by a refractive index greater than approximately 1.7 and an in-plane birefringence greater than approximately 0.2.

The present invention relates to a polypropylene composition comprising more than 80.0 to less than 100.0 wt.-% based on the total weight of the polypropylene composition of a high isotactic homopolymer of propylene (A), and more than 0.0 to less than 20.0 wt.-% based on the total weight of the polypropylene composition of a polybutylene terephthalate (B). The composition allows the achievement of electrical conductivities which are desirable for high temperature capacitor film applications. The present invention is also directed to a film comprising the polypropylene composition as well as the use of the polypropylene composition to prepare a capacitor film. Furthermore, the invention relates to a biaxially oriented film comprising the polypropylene composition as well as a method for preparing a biaxially oriented film comprising the polypropylene composition. Additionally, a capacitor comprising the biaxially oriented film is provide.

The invention provides a preparation method of a high-elastic polyester yarn, which comprises the following steps: S10: providing a pre-oriented yarn which is composed of a polyethylene glycol terephthalate component and a polybutylene terephthalate component, the polyethylene glycol terephthalate component and the polybutylene terephthalate component are distributed on the cross section in a parallel or eccentric skin-core manner; s20, the pre-oriented yarn is fed into a false twist texturing machine; s30, enabling the yarns to pass through a texturing hot box of a false twist texturing machine, wherein the temperature of the texturing hot box is set to be 240-255 DEG C; s40, the running tension of the yarn in the deformation hot box is controlled to range from 0.5 cN to 2.0 cN by adjusting the speed ratio of feeding to output; and S50, after the yarn leaves the deformation hot box and before the yarn enters the false twister, the yarn is cooled through a water bath cooling device, and the water temperature of the water bath cooling device is 20-25 DEG C. The polyester yarn prepared through the preparation method is high in structural stability, and the elastic recovery rate and the bulkiness are not prone to being reduced.

The application provides a polyester composite material and a preparation method and application thereof, the polyester composite material comprises polybutylene terephthalate, polycarbonate, a bromine-containing flame retardant, a synergistic flame retardant and a toughening agent in specific proportions, and the bromine-containing flame retardant comprises a combination of at least two of brominated epoxy resin, brominated polycarbonate or brominated polystyrene; by selecting polybutylene terephthalate and polycarbonate for collocation, and adding at least two specific bromine-containing flame retardants and synergistic flame retardants for flame-retardant modification, the obtained polyester composite material not only has excellent flame-retardant performance, but also has a low amount of die drool when being extruded in an extruder die, thereby effectively avoiding the problem that the die drool is carbonized at high temperature and then flows into the product to contaminate the product, and effectively improving the product quality of the finally obtained polyester composite material.

The present application provides a polybutylene terephthalate resin composition, a preparation method therefor, and a use thereof. The polybutylene terephthalate resin composition comprises, in parts by weight, the following components: 45-56 parts by weight of polybutylene terephthalate, 10-16 parts by weight of a halogen-free flame retardant, 2-6 parts by weight of a halogen-free synergist, 25-35 parts by weight of glass fibers, 0.4-1.5 parts by weight of a stabilizer, and 0.3-2 parts by weight of a modifier. In the polybutylene terephthalate resin composition provided by the present application, individual components and the synergistic compounding between components are screened, such that the polybutylene terephthalate resin composition has both excellent glow wire performance and tensile strength, as well as a good injection molding appearance, and can be applied in the field of electronics and electrical engineering.

The invention discloses a method for recovering terephthalic acid and succinic acid by hydrolyzing and oxidizing waste PBT (polybutylene terephthalate). The method comprises the following steps: (1) pretreating a waste PBT material to obtain a PBT raw material; (2) adding the PBT raw material, water, an oxidizing agent and a catalyst into a reactor, and carrying out one-step hydrolysis oxidation reaction under the conditions of high temperature and high pressure at the reaction temperature of 180-300 DEG C under the reaction pressure of 0.1-8 MPa for 2-12 hours to obtain a reaction mixture containing terephthalic acid and succinic acid; and (3) separating and purifying the reaction mixture to respectively obtain terephthalic acid and succinic acid products. The method provided by the invention can realize one-step hydrolysis and oxidation of PBT to obtain terephthalic acid and succinic acid products, simplifies the process, and reduces equipment investment and energy consumption; and moreover, recycling and high-added-value utilization of the waste gas PBT are also realized.

The present application relates to polybutylene terephthalate (PBT) material toothbrush filament technical field, specifically relates to a kind of multifilament version anti-lodging PBT monofilament and preparation method thereof;The preparation method is realized with the basic concept of multifilament to realize the basic form of monofilament, in the drawing process, every three monofilaments are gathered into a multifilament, in the subsequent water cooling, oiling etc. Process path, with the mode of multifilament, drafting, winding forming are completed.In the condition that monofilament specification remains unchanged, corresponding design is carried out to production process, and the quality indexes such as breaking strength, breaking strength variation coefficient, breaking elongation, breaking elongation variation coefficient of monofilament are controlled.In the realization equipment efficiency is improved three times target, product quality is upgraded, and the anti-lodging performance of PBT monofilament is improved.

A polyester resin composition exhibits high heat resistance, low gas content, and the ability to significantly suppress mold contamination during continuous molding and to inhibit flow marks. The polyester resin composition comprises: a polyester resin A containing 82-88% by mass of polybutylene terephthalate resin and 12-18% by mass of polyethylene terephthalate resin; an organometallic acid salt B, selected from one or both of alkali metal organometallic acid salts and alkaline earth metal organometallic acid salts; 1-13 parts by mass of an inorganic filler C with an average particle size of 0.05-3 μm relative to 100 parts by mass of the polyester resin A; and 0.000005-0.05 parts by mass of one or both of alkali metal atoms and alkaline earth metal atoms relative to 100 parts by mass of the polyester resin A; and the content of linear oligomers such as polybutylene terephthalate is less than 1000 mg / kg.

The invention discloses a production method of a PA / PE high-barrier composite film bag. The composite film bag comprises an outer layer, a middle layer and an inner layer, the outer layer is prepared from PA6, glass fibers, maleic anhydride grafted polyethylene, an antioxidant, a slipping agent, an ultraviolet light absorber, titanium dioxide, nano silicon dioxide and polyimide; the middle layer is prepared from EVOH (Ethylene Vinyl Alcohol), polyamide-imide, nano montmorillonite, maleic anhydride grafted polypropylene, an antioxidant, a slipping agent, terpene resin, polyvinylidene chloride and polybutylene terephthalate; the inner layer is prepared from HDPE, LLDPE, mPE, an antistatic agent, silicon dioxide, dioctyl phthalate, an antibacterial agent and polylactic acid. The composite film bag prepared by the invention not only has high barrier property and good strength, but also has various functions.

The invention discloses a plant-based water filtering material and a preparation method thereof, and relates to the technical field of filtering materials. When the plant-based water body filtering material is prepared, 4-(10, 15, 20-triphenyl porphyrin-5-yl) aniline sequentially reacts with acrylic acid-2, 3-epoxypropyl ester and zinc acetate to obtain an alkenyl porphyrin zinc complex; the preparation method comprises the following steps: reacting chitosan with an alkenyl porphyrin zinc complex to obtain modified chitosan; reacting the oxidized reed carbon with butyl trimethyl ammonium chloride to obtain modified reed carbon; preparing a spinning solution from polybutylene terephthalate, the modified chitosan and the modified reed carbon, and performing electrostatic spinning to obtain a fiber membrane; itaconic acid and alkenyl benzisothiazolinone are prepared into a finishing solution; and finishing the fiber membrane with the finishing liquid to obtain the plant-based water filtering material. The plant-based water filtering material prepared by the invention can adsorb and catalytically degrade organic dyes in wastewater and adsorb heavy metals, and also has an antibacterial effect.

The present invention relates to novel carbodiimides, to a process for their production, and to the use of the novel carbodiimides in ester-based polyols, in polyethylene terephthalate (PET), in polybutylene terephthalate (PBT), in polytrimethylene terephthalate (PTT), in copolyesters, in thermoplastic polyester elastomers (TPE E), in ethylene vinyl acetate (EVA), in polylactic acid (PLA) and / or in PLA derivatives, in polybutylene adipate terephthalate (PBAT), in polybutylene succinate (PBS), in polyhydroxyalkanoates (PHA), in blends, in triglycerides, in thermoplastic polyurethanes, in polyurethane elastomers, in PU adhesives, in PU casting resins, for PU coatings or in PU foams as stabilizers.

Depolymerization of polyalkylene terephthalate resin using Alcosilis, providing a superior depolymerization method. [Solution] The method for depolymerizing a polyalkylene terephthalate resin according to the present disclosure is a method for depolymerizing a polyalkylene terephthalate resin by alcoholization of the polyalkylene terephthalate resin, wherein the polyalkylene terephthalate resin includes a polybutylene terephthalate resin, and the alcohol used for alcoholization contains tetrahydrofuran in a proportion of more than 0 ppm by mass and 100,000 ppm or less by mass.

A polyester film includes a polyester (A) composed mainly of polybutylene terephthalate and a polyester (B) composed mainly of polyethylene terephthalate, wherein a mass ratio (A / B) between the polyesters (A) and (B) is 70 / 30 to 55 / 45, a dry heat shrinkage rate (B) through heat treatment at 200° C. for 15 minutes is 35% or less in any of four directions (0°, 45° 90° and 135°) on the film surface, a difference between a maximum value and a minimum value of these dry heat shrinkage rates is 5% or less, a thickness variation in the four directions is 10% or less, and a crystallization index shown in DSC measurement is 25 to 55 J / g.

Thermoplastic polymer compositions are disclosed that exhibit a flame retardant rating of V-0 at a thickness of 0.8 mm, and exhibit a comparative tracking index of 600 V. The polymer composition may include a glass reinforced polyester polymer, i.e., a polybutylene terephthalate polymer. In addition to one or more insulating aids, a flame retardant composition is also combined with the polymer composition.