Abstract: The present invention relates to novel polymeric compositions of matter and their use. Said polymeric compositions of matter are surface active endgroup-containing polymers that comprise a linear base polymer having covalently bonded surface active endgroups of a nature and present in an amount such that said polymers have a surface or interfacial tension that differs by at least 1 dyne/cm from the surface or interfacial tension of an otherwise identical polymer that does not contain said covalently bonded surface active endgroups. The novel linear polymers according to the present invention are particularly suitable for use in the manufacture of medical devices, and especially of medical devices intended to be used in contact with bodily fluids such as blood. Examples of such medical devices include catheters and artificial hearts.

Abstract: The present invention relates to electrostatic dissipative polymeric compositions comprising a polyether polyurethane which can be blended with one or more base polymers. In some applications, the polyurethane is useful without further blending. Further, the polyurethane blends can be blended with glass beads or glass fibers which have a synergist effect when combined with the electrostatic dissipative agent.

Abstract: Described are moisture-curing alkoxysilane-terminated polyurethanes which can be obtained by reacting polyurethane prepolymers with a mean NCO functionality of at least 1 but less than 2 with special sulfur-free alkoxysilanes, reacting with substantially all the free NCO groups. Also described is the use of these compounds as sealing and/or adhesive compositions.

Abstract: Colored or colorless aqueous nail polish containing particles of polyester-polyurethane which are anionic in dispersion, and in which the particle size is between 2 and 40 nm, and the hardness (as measured using a Persoz' clock) of the film produced after drying for 24 hours at 30.degree. C. and 50% relative humidity from a 300 .mu.m-thick layer of an aqueous dispersion of said particles containing 28% dry matter is between 50 and 300 seconds.

Abstract: The invention relates to a process for the treatment of the periphery of a glass, more particularly an encapsulated glass, which consists of treating part of the surface of the glass by at least one silane and a composition able to form a layer having free OH groups. This process is useful for treating glass so that a resin, such as a polyurethane, upon contact with the treated glass will readily adhere and bond to the glass. The treated glass can be fitted into car body bays or openings.

Abstract: This invention is directed to a process for preparing grafted organic polyester of phosphoric acid, incorporated into water-borne coating compositions, reducing remarkably the tendency of aluminum flake pigments to react with the aqueous medium of the compositions, resulting in generation of hydrogen. This can be obtained by grafting the reaction product from the reaction of an orthophosphorus derivative with a compound which contains in the molecule an epoxide group and aromatic or alicyclic group, to a pre-polymer having isocyanate group as an end group and an ethyleneoxide group. The grafted organic polyester of phosphor acid has excellent dispersity with pigments and results in satisfactory adhesion with resin as a binder because it prevents pigments from contacting with water during water dispersing.

Abstract: The invention relates to a new polyamine of the following composition: ##STR1## wherein 1.gtoreq.n.gtoreq.6, R represents the hydrocarbon radical of a (cyclo)aliphatic, araliphatic or aromatic diisocyanate having 6-20 C atoms or a trimer thereof andwherein when 2.gtoreq.n.gtoreq.6,R.sup.1 represents an n-valent organic radical such as is formed by removal of n OH groups from a polyhydroxy compound which optionally contains ether oxygen atoms and has an average molecular weight Mn of between 60 and 5,000; andwhen n=1,R.sup.1 represents ##STR2## It furthermore relates to a process for the preparation of a polyamine, in which certain diisocyanates, adducts of diisocyanates with polyols or trimers thereof are reacted with the Schiff base of the following composition: ##STR3## wherein R.sup.2 =H or a branched or unbranched C.sub.1-14 -alkyl radical and R.sup.3 =a branched or unbranched C.sub.1-14 -alkyl radical, an C.sub.1-14 alkyl-substituted phenyl radical or a C.sub.1 -C.sub.

Abstract: Moisture-hardening one-component polyurethane paints for coating elastomeric parts, consisting of polyfunctional isocyanate compounds, solvents and, optionally, auxiliaries and/or coupling agents, which contain reactive polysiloxanes and reactive surfactants for improving surface slip, may be applied by a simple painting process to elastomers, particularly apolar elastomers, for example based on styrene-butadiene rubber or polyethylene-propylene-diene and, after drying, have an optically smooth surface with good surface-slip properties with respect to glass and no abrasive effect.

Abstract: A biocompatible, hydrophilic, segmented block polyurethane copolymer which comprises 5 to 45 wt % of a hard segment and 95 to 55 wt % of a soft segment selected from a hydrophilic, hydrophobic and amphipathic oligomer is disclosed. The copolymer is capable of forming a non-porous, semi-permeable film of a tensile strength greater than 300 and up to 10,000 psi, and has an ultimate elongation greater than 300% and up to 1,500% and a water absorption such that the sum of the volume fraction of absorbed water and the hydrophilic volume fraction of the soft segment exceeds about 100% and is up to about 2,000% of the dry polymer volume. The film is permeable to cell nutrients and waste molecules of up to about 6,000 to 600,000 molecular weight and is substantially impermeable to cells and particulate matter. A non-porous, semi-permeable, biocompatible film is formed from the block copolymer of the invention in the form of a flexible sheet or a hollow fiber.

Abstract: A blend of isocyanate-terminated polyurethane prepolymers comprising: (a) a first prepolymer which comprises the reaction product of an at least essentially semicrystalline hydroxy-functional material and a polyisocyanate; (b) a second prepolymer which comprises the reaction product of a poly(tetramethylene glycol)ether and a polyisocyanate; and (c) a third prepolymer which comprises the reaction product of an essentially amorphous hydroxy-functional material and a polyisocyanate. The blend may also include a fourth prepolymer which comprises the reaction product of a slightly branched hydroxy-functional material and a polyisocyanate.

Abstract: The invention relates to a cathodic electro-dipping process wherein the electro-dipping primer employed contains a crosslinking agent which can be obtained by(I) reacting, in a first stage,(a) diphenylmethane diisocyanate and(b) a monoalcohol or a mixture of monoalcohols to give an intermediate product (A) containing isocyanate groups, and(II) reacting this intermediate product (A) in a second stage with(c) a polyol or a mixture of polyols to give an intermediate product (B) containing hydroxyl groups which(III) is reacted in a third stage either with(d) a cycloaliphatic, aliphatic or araliphatic polyisocyanate or a mixture of such polyisocyanates and(e) a monofunctional masking agent or a mixture of such masking agents or with(f) a partially-masked polyisocyanate prepared from (d) and (e)to give a crosslinking agent which is free from isocyanate groups.

Abstract: A novel polyurethane formulation especially effective as a corrosion preventing coating for metallic substrates. The polyurethane is prepared by mixing two components, one being a mixture of high and low molecular weight polyol compounds and the other being a polymeric methylene polyphenyl isocyanate (MDI).

Abstract: A moisture-curable urethane-based sealing composition is made up of an urethane prepolymer and a polyurethane compound blended together in specified amounts. The urethane prepolymer is derivable by reacting a selected class of polyether polyols with a selected class of polyisocyanate compounds. The polyurethane compound is available by reacting a selected class of polyether or polyester polyols with a selected class of polyisocyanate compounds, followed by reaction of the resulting prepolymer with a selected class of monoalcohols to thereby binder all isocyanate groups in the prepolymer. The ultimate sealant is adequate in initial adhesion strength, low in glass transition temperature and resistant to moist heat.

Abstract: A process for the preparation of recyclate polyols obtained by glycolysis of polyurethanes and/or polyurea-polyurethanes comprises metering in monofunctional and/or difunctional glycidyl ethers over the entire course of the reaction; the low-amine recyclate polyols obtained in this way are used for the preparation of cellular or noncellular polyurethanes.

Abstract: Compounds containing alcoholic hydroxyl groups suitable as a starting material for the isocyanate polyaddition process by the alcoholysis of polyisocyanate polyaddition products are produced. Polyurethane urea or polyurea waste products having a molar ratio of urea groups to urethane groups of from 1:20 to 1:0 are heated in size reduced form to temperatures of from 120.degree. to 250.degree. C. together with B) polyhyhdric alcohols in the molecular weight range of from 62 to 250 in a ratio by weight of A:B of from 3:1 to 1:10. At least 10% of the polyhydric alcohol B put into the process is subsequently removed by distillation under reduced pressure. A total of up to 1000% by weight, based on the weight of polyurethane urea or polyurea waste A, of one or more polyhydroxy compounds having a molecular weight above 250 which is (are) not volatile under the distillation conditions may optionally be added to the mixture before and/or after removal of the excess alcohol B by distillation.

Abstract: Process for preparing a flexible foam by reacting an isocyanate prepolymer having a free NCO content of 2-15% by weight, an isocyanate prepolymer having a free content of 25-31% by weight and an isocyanate-reactive composition comprising water.

Abstract: A polymer polyol composition comprising a continuous phase, a disperse phase within the continuous phase, and a dispersant to enhance the stability of the polymer polyol is disclosed. The dispersant is a grafted polyol-polyacrylate dispersant comprised of a isocyanate vinyl monomer/ethylenically unsaturated monomer random copolymer and a polyoxyalkylene polyether, wherein the random copolymer and the polyoxyalkylene polyether are connected through at least one urethane graft site.Methods of preparing the polymer polyol composition and the grafted polyol-polyacrylate dispersant are provided. The polymer polyol compositions have low viscosities as well as high stability and may be prepared with high levels of dispersed vinyl polymer and high styrene:acrylonitrile ratios in the dispersed vinyl polymer. The polymer polyol compositions are useful for the preparation of polyurethanes, particularly polyurethane foams.

Abstract: Amine-containing, water dispersible polyurethanes made by the following process: (1) in a reactive diluent such as acrylate, methacrylate, acrylonitrile monomer, low viscosity epoxy compound or epoxy resin, or mixture thereof, using an excess amount of polyisocyanate to react with polyol to form NCO-terminated urethane prepolymer; (2) adding hydroxy alkyl acrylate or hydroxy alkyl methacrylate monomer to react with the prepolymer in step (1) to convert its -NCO end group into alkyl acrylate or alkyl methacrylate end group; and (3) using an excess amount of polyamine to react with the alkyl (meth)acrylate-terminated prepolymer in step (2) and the reactive diluent and the residual hydroxy-containing monomer in step (2), if any. The polyurethane can be mixed with a crosslinking agent having multi-epoxy or blocked polyisocyanate functionalities, to prepare a stable aqueous coating composition.

Abstract: This invention relates to a process for producing a moisture curable silyl-terminated polymer which comprises the steps of: (a) reacting a terminally-unsaturated monol (preferably a polyether or polyester monol) with a polyfunctional hydroxyl-reactive compound selected from the group consisting of polyisocyanates and organic polacyl compounds in a molar ratio of one mole of monol for each equivalent of functionality on said polyfunctional hydroxyl-reactive moiety, to provide a terminally-unsaturated polymer having terminal unsaturation at each end thereof; and (b) reacting said terminally-unsaturated polymer with a dialkoxyalkylsilane to form a dialkoxyalkylsilylterminated polymer capable of curing upon contact with moisture.

Abstract: A one-component, moisture-curable polyurethane-based adhesive composition useful for affixing glass panels directly to electrocoat painted metal substrates or over a primer comprises a polyurethane base polymer containing an electrocoat adhesion promoter. The sealant composition has fast cure times at ambient temperatures and forms a strong bond directly to electrocoat painted metal substrates without the need for a sealant primer.

Abstract: A composite metal powder composition according to the present invention is a composition containing composite metal powder obtained in such a manner that an isocyanate compound is chemically bonded to the surface of surface-treated metal particles and a phosphorus compound is further chemically bonded to the isocyanate compound through an urethane bond and can be used as an excellent pigment for an aqueous paint.

Abstract: Process for preparing a flexible foam by reacting an isocyanate prepolymer having a free NCO content of 2-15% by weight, an isocyanate prepolymer having a free content of 25-31% by weight and an isocyanate-reactive composition comprising water.

Abstract: A coating composition for a substrate to be imprinted with an image by means of sublimation or heat transfer that comprises a mixture of an epoxy resin and a blocked polyisocyanate in an equivalent-weight ratio in a range from 0.5 to 1.8 in appropriate solvents When cured, this composition results in a low glass-transition-temperature polyurethane that is smooth, colorless, tough, clear and glossy, capable of accepting a perfect reproduction of the transfer print. Upon exposure to hot water during dishwashing, the unreacted polymer-bound isocyanate groups further react to form a skin of highly crosslinked polymer chains. The skin creates a barrier to the deleterious effects of water on adhesion and to the diffusion of sublimation dyes out of the coating. The resulting transferred image is colorfast and the coating has strong adhesion to ceramic surfaces to survive repeated mechanical dishwashing.

Abstract: This invention relates to a process for producing a moisture curable silyl-terminated polymer which comprises the steps of: (a) reacting a terminally-unsaturated monol (preferably a polyether or polyester monol) with a polyfunctional hydroxyl-reactive compound selected from the group consisting of polyisocyanates and organic polacyl compounds in a molar ratio of one mole of monol for each equivalent of functionality on said polyfunctional hydroxyl-reactive moiety, to provide a terminally-unsaturated polymer having terminal unsaturation at each end thereof; and (b) reacting said terminally-unsaturated polymer with a dialkoxyalkylsilane to form a dialkoxyalkylsilyl-terminated polymer capable of curing upon contact with moisture.

Abstract: A vinyl chloride resin composition which comprises 100 parts by weight of a reaction product of a polyol-containing vinyl chloride polymer with an isocyanate compound, the urethane content in the reaction product being 30-60% by weight, 10-300 parts by weight of a vinyl chloride resin comprising 8-90% by weight of a tetrahydrofuran-insoluble polyvinyl chloride gel portion and the remainder of a tetrahydrofuran-soluble portion and 0-200 parts by weight of a plasticizer.

Abstract: A non-isocyanate flexibilizer additive is provided which finds utility in coating systems such as alkyds, polyesters, acrylic/polyester, alkyd/acrylic, carboxy/epoxy, polyether/urethane, epoxy/polyester, other epoxy, and urea and melamine formaldehyde systems. The non-isocyanate functional flexibilizer has the formula; B--C(O)--NW--A--NX--C(O)--K wherein A is selected from the group consisting fundamentally of polyesters, polyamides, polyureas, polyurethanes, acrylics; biuret, allophonate and urethane extended polyesters; wherein B and K are selected from the group consisting of --OR and --Z--R'--SiOR".sub.(3-n) R"".sub.n wherein R' is a divalent lower alkyl radical of from 1 to 18 carbon atoms, R is a lower alkyl radical of from 1 to 18 carbon atoms, Z is a member selected from the group consisting of S and NR", W and X are selected from H and lower alkyl radicals of from 1 to 10 carbon atoms, wherein R", R" and R"" are H or a lower alkyl radical of from 1-18 carbon atoms, and wherein n is 0, 1 or 2.

Abstract: A polyurethane composition useful as a molding composition is prepared from (1) an adduct derived from the reaction product of a polyepoxide and a single epoxide reactive group-containing compound, or the reaction product of a monoglycidyl ether and an epoxide reactive groups-containing compound, (2) a polyisocyanate, and (3) optionally an isocyanate-reactive compound; wherein at least one of the adduct or polyisocyanate contains a rodlike mesogenic moiety.

Abstract: A quick-setting, moisture-curing hot-melt polyurethane composition having a first polyether-based polyurethane prepolymer having a Tg above room temperature and a second polyurethane prepolymer with a Tg below room temperature, the first prepolymer being prepared from a low molecular weight polyether; preferably the second prepolymer is also polyether based and prepared from a high molecular weight polyether.

Abstract: In thermoplastic elastomers selected from the group consisting of the thermoplastic polyurethanes, of the polyetheresters and of the polyetheramides which are derived from polyetherpolycarbonatediols as diol components, the polyetherpolycarbonatediols used are reaction products of phosgene, dialkyl carbonates having C.sub.1 -C.sub.4 -alkyl groups or cyclic carbonates having C.sub.2 -C.sub.4 -alkylene bridges or mixtures thereof with mixtures ofa.sub.1) from 10 to 100 mol % of polyoxytetramethylenediol having a number average molecular weight M.sub.n of from 150 to 500 anda.sub.2) from 0 to 90 mol % of polyoxyalkylenediols which differ from a.sub.1) and have C.sub.2 -C.sub.8 -alkylene groups, aliphatic alkanediols of 2 to 14 carbon atoms, alicyclic alkanediols of 3 to 14 carbon atoms or alkylene oxides of 2 or 3 carbon atoms, or mixtures thereof.

Abstract: A polymeric compound is derived from a polyhydric material and has pendant sulphonate groups of the general formula ##STR1## and pendant alkyl urethane groups of the formula ##STR2## where X is an aliphatic, aromatic, carboxylic or heterocyclic group; Y is hydrogen, halogen or an alkyl, aryl, alkoxy, aryloxy or aralkyl group, CO.sub.2.sup.- Z.sup.+, CO.sub.2 R or SO.sub.3.sup.- Z.sup.+ ; Z.sup.+ is a cationic counter ion and R is hydrogen alkyl, alkylene, aryl or aralkyl group.

Abstract: This invention relates to a polypropenyl ether having the formula ##STR1## wherein m and s each independently have a value of from 1 to 6; R is alkyl or phenyl optionally substituted with lower alkyl or halogen; A is C.sub.1 to C.sub.12 alkylene, aryl or --R.sub.1 OR.sub.2 --, optionally substituted with lower alkyl, haloalkyl, halogen or phenyl; one of p and p' has a value of one and the other is zero; R.sub.3 is C.sub.1 to C.sub.20 alklylene substituted with expression indicated by n and n has a value of from 1 to 10.

Abstract: A primerless, one-component, moisture-curable polyurethane-based adhesive composition useful for affixing glass panels directly to electrocoat painted metal substrates comprises a polyurethane base polymer containing an electrocoat adhesion promoter. The sealant composition has fast cure times at ambient temperatures and forms a strong bond directly to electrocoat painted metal substrates without the need for a sealant primer.

Abstract: This invention pertains to the polyurethane composition with hydrophilicity and hydrolysis resistance. The purpose of this invention is achieved by:1) A polyurethane molecule containing at least one acidic hydrophilic group in the molecule which is neutralized with piperidine derivatives and piperazinone derivatives, or2) A mixture containing polyurethane and compounds(s) having at least one acidic hydrophilic group which is neutralized with piperidine derivatives and piperazinone derivatives.The invention polyurethane compositions which have excellent hydrolysis resistance and rupture strength are useful for adhesives, paints, and bonding agents for magnetic recording media.

Abstract: The invention relates to ternary thermoplastic mixtures of polycarbonates, polyurethanes and graft polymers and, optionally, standard additives and to processes for the production of these mixtures.

Abstract: The strength and integrity of hydrophilic polyurethane resins prepared by reacting a diol component, an organic chain extender and an organic diisocyanate are improved by critical selection of the diol component, the amount of water in the reaction mixture and the mole rations of the reactants. The diol component is at least one of (1) a long chain poly(oxyethylene) glycol of molecular weight above 2500 and (2) a medium chain poly(oxyethylene) glycol or polyester glycol of 250-2500 molecular weight. The chain extender is a difunctional compound having a molecular weight of less than 250. The amount of water in the reaction mixture is 0.5 to 2.5 weight % and the urea content of the resins is from about 13.6 to 33.7 weight %.

Abstract: Ester-modified poly(alkylene carbonate) polyahls comprising the residues of at least one polyahl, polyalkyleneoxy moieties, poly(alkylene carbonate) moieties, the residues of at least one ester of a carboxylic acid, and a plurality of active hydrogen end group are disclosed. The ester-modified poly(alkylene carbonate) polyahl has a number average molecular weight higher than the number average molecular weight of any known poly(alkylene carbonate) polyahl comprising the same monomeric components. Also disclosed are isocyanate-functional prepolymers of these ester-modified poly(alkylene carbonate) polyahls formed by reactions of the ester-modified poly(alkylene carbonate) polyahls of this invention with excess organic polyisocyanates. Urethane/urea polymers formed by the reactions of the isocyanate-functional prepolymers with polyahls are also disclosed.

Abstract: This invention provides a mold release composition copmrising (1) a compound or a polymer having at least one of perfluoroalkyl groups having 4 to 20 carbon atoms and perfluoroalkenyl groups having 4 to 20 carbon atoms, and (2) a ladder polymer of organosilsesquioxane.

Abstract: This invention relates to polymeric compositions derived by the polycondensation of heteroatom containing perfluoroalkyl terminated neopentyl glycols, and diamino, dihydroxy, or dimercapto-polysiloxanes and optionally other diols, dimercaptans or diamines with organic diisocyanates; and blends of polycondensation polymers with oxime-blocked organic polyisocyanates. These compositions and blends are useful as coatings on glass, wood, paper, leather and especially textiles.

Abstract: The cross-linking or curing of thermosetting resins and of hot curable elastomers is carried out by heating the material or the article comprising the resin (or the elastomer) by saturated vapor of the commercial perfluoropolyether having an average boiling point corresponding to the temperature necessary for the cross-linking and having a point range not exceeding 12.degree. C. (measured according to ASTM D 1078) in the presence of a chlorofluorohydrocarbon secondary vapor.

Abstract: A curing composition showing improved drying characteristics of an alkyd coating which comprises:(A) an oxyalkylene polymer having at least one silicon atom-containing group which has a hydroxyl group or a hydrolyzable group bound to a silicon atom and is capable of crosslinking by forming a siloxane bond;(B) a polymeric plasticizer and/or a viscous plasticizer; and(C) an air curing compound.

Abstract: Triazine compounds are disclosed which are useful for imparting UV screening properties to polymers of the formula: ##STR1## wherein R is an electron withdrawing group; R.sub.1 is H, ##STR2## where R.sub.3 is an alkyl group having from one to about six carbon atoms; and R.sub.2 is selected from H and CH.sub.3, also disclosed are polymer compositions having improved UV screening properties containing said triazine compounds.

Abstract: The present invention relates to the use of polysiloxanes containing amino groups as additives for improving levelling and wetting of polyurethane-based coating compositions applied to plastic substrates. The present invention additionally relates to the coated plastic substrates.

Abstract: The stability and physical properties of high molecular weight emulsion polymers are improved by the addition of a low molecular weight support resin during the emulsion polymerization process. The resin is soluble or dispersible in water or alkali and has a number average molecular weight between 500 and 20,000.

Abstract: This invention, therefore, relates to the field of polyurethane coatings for use in automobile basecoat/clearcoat systems. In particular, this invention relates to water-dispersible polyurethane resins having polyether sidechains which may be utilized in basecoat compositions as principal resins or grind resins. These polyurethane resins may be laterally stabilized or terminally stabilized. The terminally stabilized resins of this invention are preferably employed as principal resins in basecoat compositions.

Abstract: The present invention relates to an adhesive composition comprising 100 parts by weight of a polyester-polyurethane having an isocyanate group (--NCO) and 0.002-20 parts by weight of a halogenating agent, suitably used for the adhesion of polyolefin materials which are difficult to glue, such as car molding and base materials for electrostatic flocked products, the adhesion of trimming, the adhesion of rubber products and others.

Abstract: A graft copolymer produced by polymerizing an ethylenically unsaturated monomer in the presence of a fluorine-containing resin having reactive double bonds via a urethane linkage is excellent in transparency and pigment dispersibility and can provide a coating composition excellent in weather resistance.

Abstract: Organopolysiloxane compositions curable into elastomeric state even in the absence of atmospheric moisture, notably in a confined environment, and well adopted for the production of seals, include an acyloxy crosslinking agent and a natural or synthetic hydrogel hardening agent.

Abstract: Organopolysiloxane compositions curable into elastomeric state even in the absence of atmospheric moisture, notably in a confined environment, and well adopted for the production of seals, include a ketiminoxy crosslinking agent and a natural or synthetic hydrogel hardening agent.

Abstract: A urethane sealant or coating composition is made from a physical blend of a polypropyleneoxide polyol intermediate and an organic-silicone block copolymer based polyol intermediate. The urethane prepolymer is made by reacting the physical intermediate blend with a polyisocyanate and preferably blocking the same with blocking agents such as phenols to prevent reaction with moisture in the air. Cure is effected through the utilization of curing agents such as polyamines or polyimines, for example, diamines, amine terminated polyethers, ketimines, aldimines, and the like. The sealant composition can contain various fillers, organosilanes, and the like. The prepolymers of the present invention generally have improved elongation and reduced modulus. Either a one-part or a two-part system can be utilized.

Abstract: A one-part curing composition comprising a compound (a) having two or more structural groups, per molecule, expressed by the general formula: ##STR1## wherein R.sup.1, R.sup.2, and R.sup.3 are groups selected from an alkyl group having 1 to 6 carbon atoms, a phenyl group, and a chloromethyl group, and a polymer (b) having two or more isocyanate groups per molecule, has a good stability in storage under conditions which exclude moisture and humidity, and which further cures in the presence of humidity. This composition does not foam under high temperatures and humidities and has a good heat resistance.