Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/49—Phosphorus-containing compounds
  • C08K5/51—Phosphorus bound to oxygen
  • C08K5/52—Phosphorus bound to oxygen only
  • C08K5/524—Esters of phosphorous acids, e.g. of H3PO3
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L69/00—Compositions of polycarbonates; Compositions of derivatives of polycarbonates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L69/00—Compositions of polycarbonates; Compositions of derivatives of polycarbonates
  • C08L69/005—Polyester-carbonates

Definitions

• the invention relates to blends of a polycarbonate resin with a polyester resin.
• Aromatic polycarbonates are well known and exhibit properties of extreme toughness, transparency, resistance to burning and in general, maintenance of useful properties over a wide temperature range.
• polycarbonate has an increased Y.I. yellowness index, after exposure to light. Hence, it is desirable to enhance the weatherability of polycarbonate.
• polycarbonates exhibit high impact strength, it is desirable to obtain even higher impact strength.
• U.S. Patent 4,391,954 to Scott describes an aromatic carbonate polymer having improved hydrolysis resistance.
• the polycarbonate includes a polyester polymer derived from cyclohexanedimethanol.
• column 3, lines 4 to 7, "The preferred polyester resins may be derived from the reaction of either the cis- or trans- isomer (or a mixture thereof) of 1,4-cyclohexanedimethanol with a mixture of iso- and terephthalic acids.”
• Patent 5,486,562 describes UV-stable weatherable molding compositions based upon cycloaliphatic diacid derived polyester materials containing impact-modifying elastomeric polymers and filler such as glass fibers, which compositions have enhanced melt flow properties while retaining good impact strength properties.
• the modulus of these compositions is low and while stiffness can'be improved with added filler, like fiberglass, impact strength is reduced.
• U.S. Patent 5,410,000 discloses molding compositions containing poly (cycloalkyl/ aryl) polyesters and mixtures thereof with other polymeric binder materials including polycarbonates, together with impact modifying polymers and reinforcing fillers.
• U.S. Patent 5,399,661 discloses molding compositions containing poly (cycloalkyl/ aryl) polyesters and mixtures thereof with other polymers, core shell impact modifiers and fillers. These aromatic cycloalkyl esters do not have good weatherability.
• U.S. Patent 5,260,379 discloses thermoplastic molding compositions comprising blends of aromatic polyester resins and styrene copolymers containing up to about 35 mol% methyl methacrylate and having good ductility and melt flow properties. Glass fiber reinforcing filler may be included as well as "impact modifiers". Specific blends containing 25, 50 and 75 weight percent of each of these styrene copolymers are disclosed but no specific impact modifier is disclosed as an additive to such blends.
• U.S. Patent 3,657,389 discloses hot melt adhesive compositions based upon polymer blends of cycloaliphatic polyesters and olefin polymers including acrylate and methyl methacrylate co-polymers. Fillers may be included but impact modifiers are not disclosed.
• U.S. Patent 5,115,016 discloses aromatic polyester resin molding compositions comprising a crystalline polyethylene terephthalate, reinforcing glass fiber and a thermoplastic poly(methyl methacrylate) modifier resin which improves the gloss and reduces warp of articles molded therefrom.
• the present invention relates to molding compositions based upon blends of thermoplastic polycarbonate resin and a thermoplastic polyester resin which have outstanding impact resistance, good processabilitiy, and transparency. The impact is greater than would be expected from a just a mixture of the components.
• the polycarbonate polyester molding compositions of the present invention comprise a polycarbonate resin component and a cycloaliphatic polyester component.
• the ductile polycarbonate component is an aryl polycarbonate, a polyester carbonate or a "soft segment" aliphatic- polyester carbonate.
• the cycloaliphatic component is substantially devoid of aromatic constituents.
• a miscible resin blend comprising a ductile polycarbonate, aromatic polyester carbonate or aliphatic polyester carbonate and a cycloaliphatic polyester resin wherein ratio of polyester to ductile resin is from about 50 to 50 to about 95 to about 5.
• the polyester resin comprises a polyester having repeating units of the formula I:
• R and R 1 are cycloakyl or cycloalkyl containing radicals.
• the polyester is a condensation product where R is the residue of a cycloalkane containing diol having 6 to 20 carbon atoms or chemical equivalent thereof, and R 1 is the decarboxylated residue derived from a cycloalkane containing diacid of 6 to 20 carbon atoms or chemical equivalent thereof.
• the resulting blend has a Notched Izod (NI) as determined by
• a miscible polycarbonate/ polyester blend of the present invention exhibits a surprisingly low notch sensitivity with Notched Izod values as high as 25 ft. lbs./ in. at 23°C and surpass the ductility of neat polycarbonate by up to 65 percent. More surprisingly, this effect is achieved without the use of an impact modifier so that the resulting blends are transparent.
• Additional ingredients may include rubbery modifiers such as core shell, graft or linear, random and block copolymers.
• the ductile resin which is a resin selected from the group consisting of
• Ar 1 is a divalent aromatic radical residue of the dihydric phenol employed in the preparative polymerization reaction of the polycarbonate.
• Preferred divalent residue of dihydric phenols, Ar' are represented by the general formula:
• Ar is a divalent hydrocarbon radical containing from 1 to about 15 carbon atoms or a substituted divalent hydrocarbon radical containing from 1 to about 15 carbon atoms; each X is independently selected from the group consisting of hydrogen, halogen, and a monovalent hydrocarbon radical such as an alkyl group of from 1 to about 8 carbon atoms, an aryl group of from 6 to about 18 carbon atoms, an aralkyl group of from 7 to about 14 carbon atoms, an alkoxy group of from 1 to about 8 carbon atoms; and m is 0 or 1 and n is an integer of from 0 to about 5.
• Ar may be a single aromatic ring like hydroquinone or resorcinol, or a multiple aromatic ring like biphenol or bisphenol A. the more preferred dihydric phenol employed comprises greater than 70 percent by weight bisphenol A with the remairung portion comprising dihydric phenol residue of the above formula.
• Ar is a divalent aliphatic, alicyclic or aromatic radical, or mixtures thereof of the condensation product from a dicarboxcylic acid or derivative thereof.
• Ar is a C6-C20 aryl radial comprising a decarboxylated residue derived from an aromatic dicarboxcylic acid.
• Ar is most preferably the residue from iso- and terephthalate or mixtures thereof having the formula:
• D is an diavalent aliphatic radical of the condensation product from an aliphatic diol.
• D is a divalent alkylene radical containing 2 to 18 carbon atoms, more preferably A has the formula -(CH2)n- wherein n is an integer of from 2 to 18, more preferably from 2 to 6.
• D is the divalent aliphatic residue from the dicarboxcylic acid which results when a dihydric phenol is phosgenated in the presence of the dicarboxcylic acid or derivative thereof.
• D is an divalent alkyl radical of from C2 to C36, more preferably from to Q ⁇ , with the preferred formula -(CH2) n -.
• the preferred component a) is an aromatic carbonate homopolymer, e.g., a homopolymer derived from 2,2-bis(4- hydroxyphenyl)propane (bisphenol-A) and phosgene, commercially available under the trade designation LEXAN Registered TM from bisphenol-A.
• the preferred polycarbonates are preferably high molecular weight aromatic carbonate polymers have an intrinsic viscosity (as measured in methylene chloride at 25°C) ranging from about 0.30 to about 1.00 dl/gm.
• Polycarbonates may be branched or unbranched and generally will have a weight average molecular weight of from about 10,000 to about 200,000, preferably from about 20,000 to about 100,000 as measured by gel permeation chromatography. It is contemplated that the polycarbonate may have various known end groups.
• the impact resistance of a high impact weatherable polycarbonate/ polyester molding composition can be substantially improved by blending the previously mentioned polyester containing cycloalkyl radials to form a molding composition having a substantially greater toughness than could be predicted according to the rule of mixtures.
• the present cycloaliphatic polyesters are condensation products of aliphatic diacids, or chemical equivalents, and aliphatic diols, or chemical equivalents.
• the present cycloaliphatic polyesters may be formed from mixtures of aliphatic diacids and aliphatic diols but must contain at least 80 mole % of cyclic diacid and/ or cyclic diol components, the remainder, if any, being linear aliphatic diacids and/ or diols.
• the cyclic components are necessary to impart good rigidity, and they do not absorb UV under normal exposure conditions, thereby providing rigid molded articles having excellent weatherability properties. Aromatic components are not preferred since, to the extent they are present, they impart enhanced UV- absorbance leading to degraded weatherability properties.
• the preferred component b) is a polyester carbonate which may be represented by the following formula:
• x and y represent the respective weights of ester units and polycarbonate units based on 100 parts total weight.
• x is 0, the polyester linkages are absent and the resin is known as a polycarbonate resin.
• y is greater than about 5 percent by weight, the resin is known as a polyester carbonate resin (PEC resin).
• PEC resin polyester carbonate resin
• x is from about 60 to about 95 mole percent.
• Poly(ester-carb ⁇ nate) resins also commonly referred to as copolyester-polycarbonate resins, are copolymers of aromatic diphenols reacted with dicarboxylic acids and carbonic acid or their derivatives.
• Melt polymerization methods to make PEC resins may involve co- reacting, for example, various mixtures of dihydric phenols and ester precursors such as, for example, diphenyl derivatives of iso- and terephthalates, and their mixtures.
• Diphenyl carbonate may be introduced to prepare polyester carbonate copolymers.
• catalysts or mixtures of catalysts such as, for example, lithium hydroxide and lithium stearate can also be used to accelerate the polymerization reactions.
• the method of interfacial polymerization comprises the reaction of a dihydric phenol with diacid or derivative ester precursor and optionally a carbonate precursor, in a two phase system with catalyst and often an acid acceptor when the dicarboxylic acid and carbonate precursors are diacid halides.
• Examples of interfacial polymerization techniques can be found in U.S. Patent Nos. 3,169,121 and 4,487,896 which are incorporated herein by reference.
• reaction conditions of the preparative processes may vary, several of the preferred processes typically involve dissolving or dispersing dihydric phenol reactants in aqueous caustic, combining the resulting mixture with a suitable water immiscible solvent medium and contacting the reactants with the carbonate precursor, such as, for example, phosgene, and diacids or derivatives, such as diacid chlorides, in the presence of a suitable catalyst and under controlled pH conditions.
• the carbonate precursor such as, for example, phosgene
• diacids or derivatives such as diacid chlorides
• a catalyst may be added to the reaction mixture ' to promote the reaction.
• the catalyst typically accelerates the rate of polymerization of the dihydric phenol reactants with the carbonate/ ester precursors.
• Representative catalysts include but are not limited to, for example, tertiary amines such as triethylamine, quaternary phosphonium compounds, quaternary ammonium compounds, and the like.
• the carbonate precursors are typically a carbonyl halide, a diarylcarbonate, or a bishaloformate.
• the carbonyl halides include, for example, carbonyl bromide, carbonyl chloride, and mixtures thereof.
• the bishaloformates include the bishaloformates of dihydric phenols such as bischloroformates of 2,2-bis(4-hydroxy-3,5-dichlorophenyl)-propane, hydroquinone, and the like, or bishaloformates of glycol, and the like. While all of the above carbonate precursors are useful, carbonyl chloride, also known as phosgene, is preferred.
• any dicarboxylic acid conventionally used in the preparation of polyesters may be utilized in the preparation of poly(ester- carbonate) resins.
• the PEC used in the present invention are prepared with aromatic dicarboxylic acids, and in particular terephthalic acid, and mixtures thereof with isophthalic acid.
• the acid halides are the acid dichlorides and the acid dibromides.
• terephthalic acid or mixtures thereof with isophthalic acid it is possible to employ terephthaloyl dichloride, and mixtures thereof with isophthaloyl dichloride
• a molecular weight regulator (a chain stopper) is generally added to the reaction mixture prior to or during the polymerization reactions with carbonate and/ or ester precursors.
• Useful molecular weight regulators include, for example, monohydric phenols such as phenol, chroman-I, para-t-butylphenol, p-cumylphenol and the like.
• the proportions of reactants employed to prepare the PEC will vary in accordance with the proposed use of the blends of the invention containing this product resin.
• the amount of the ester units may be from about 0 by weight to about 90% by weight, relative to the carbonate units, preferably about 0% to about 30% by weight relative to the carbonate units.
• any dicarboxylic acid conventionally used in the preparation of polyesters may be utilized in the preparation of poly(estercarbonate) resins.
• the PEC used in the present invention are prepared with aromatic dicarboxylic acids, and in particular terephthalic acid, and mixtures thereof with isophthalic acid wherein the weight ratio of terephthalic acid to isophthalic acid is in the range of from about 5:95 to about 95:5
• the preferred PEC for use as the ingredient (b) in the blends of the present invention are those derived from reaction of bisphenol-A and phosgene with iso- and terephthaloyl chloride and having an intrinsic viscosity of about 0.5 to about 0.65 deciliters per gram (measured in methylene chloride at a temperature of 25°C).
• the Ar radical in the above formula is most often p- or m- phenylene, a cycloaliphatic or a mixture thereof.
• This class of polyester includes the poly(alkylene terephthalates). Such polyesters are known in the art as illustrated by the following patents, which are incorporated herein by reference.
• aromatic dicarboxylic acids represented by the dicarboxylated residue Ar 1 are isophthalic or terephthalic acid, l,2-di(p- carboxyphenyl)ethane, 4,4'-dicarboxydiphenyl ether, 4,4' bisbenzoic acid and mixtures thereof. Acids containing fused rings can also be present, such as in 1,4- 1,5- or 2,6- naphthalenedicar boxy lie acids.
• the preferred dicarboxylic acids are terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, cyclohexane dicarboxylic acid or mixtures thereof.
• the preferred component c), the soft segment polycarbonate exhibit a lower glass transition (Tg) temperature and improved low temperature impact strengths.
• Tg glass transition
• the Tg of the resin is reduced by the presence of diester blocks.
• U.S. patent 5,494,997 to Fontana et al describes the preparation of a thermoplastic, copolyestercarbonate by phosgenating the dihydric phenol in the presence or absence of an aliphatic dicarboxylic acid under conditions which yield an excess of chloroformate end-groups relative to phenolic or carboxylic acid moieties; and polymerizing the chloroformates with re ⁇ iaining phenols and carbonate acids or with subsequently added aliphatic dicarboxylic acid by addition of a carbonate forming reagent and a molecula weight regulator.
• the above patent is incorporated by reference into the present application.
• polyester resins of Formula I as previously set forth are typically obtained through the condensation or ester interchange polymerization of the diol or diol equivalent component with the diacid or diacid chemical equivalent component and have recurring units of the formula where R is derived from alicyclic dibasic acids and R' is derived from a alicyclic diols R':
• the preferred cycloaliphatic polyesters for use in the present molding compositions are condensation products of cycloaliphatic diols and cycloaliphatic diacids or chemical equivalents of the diacids such as the salts, esters or acid halides thereof.
• R is a cycloalkyl radical containing 6 to 20 carbon atoms and which is the residue of a cyloaliphatic alkane diol or chemical equivalent thereof; and R' is a cycloalky radical which is the decarboxylated residue derived from a cycloaliphatic diacid or chemical equivalent.
• R and R 1 are preferably cycloalkyl radicals independently selected from the following formula:
• the most preferred cycloaliphatic radical R' is derived from the 1,4- cyclohexyl diacids and most preferably greater than 70 mole % thereof in the form of the trans isomer.
• the most preferred cycloaliphatic radica R is derived from the 1,4-cyclohexyl primary diols such as 1,4-cyclohexyl dimethanol, most preferably more than 70 mole % thereof in the form of the trans isomer.
• a cycloaliphatic diol or chemical equivalent thereof and particularly 1,4-cyclohexane dimethanol or its chemical equivalents are used as the diol component, preferably a mixture of cis- to trans-isomers thereof, where the trans isomer content is 70% or more.
• esters such as dialkylesters, diaryl esters and the like.
• the diacids useful in the preparation of the aliphatic polyester resins of the present invention preferably are cycloaliphatic diacids. This is meant to include carboxylic acids having two carboxyl groups each of which is attached to a saturated carbon.
• Preferred diacids are cyclo or bicyclo aliphatic acids, for example, decahydro naphthalene dicarboxylic acids, norbornene dicarboxylic acids, bicyclo octane dicarboxylic acids, 1,4-cyclohexanedicarboxylic acid or chemical equivalents, and most preferred is trans-l,4-cyclohexanedicarboxylic acid or chemical equivalent.
• Cyclohexanedicarboxylic acids and their chemical equivalents can be prepared, for example, by the hydrogenation of cycloaromatic diacids and corresponding derivatives such as isophthalic acid, terephthalic acid or naphthalenic acid in a suitable solvent, water or acetic acid at room temperature and at atmospheric pressure using suitable catalysts such as rhodium supported on a suitable carrier of carbon or alumina. See, Friefelder et al, Journal of Organic Chemistry, 31, 3438 (1966); U.S. Pat. Nos. 2,675,390 and 4,754,064.
• They may also be prepared by the use of an inert liquid medium in which a phthalic acid is at least partially soluble under reaction conditions and a catalyst of palladium or ruthenium in carbon or silica. See, U.S. Pat. Nos. 2,888,484 and 3,444,237.
• the carboxylic acid groups are in cis- or trans-positions.
• the cis- and trans- isomers can be separated by crystallization with or without a solvent, for example, n-heptane, or by distillation.
• the cis-isomer tends to blend better; however, the trans-isomer has higher melting and crystallization temperatures and is especially preferred.
• Mixtures of the cis- and trans- isomers are useful herein as well, and preferably when such a mixture is used, the trans-isomer will comprise at least about 70 parts by weight.
• a copolyester or a mixture of two polyesters may be used as the present cycloaliphatic polyester resin.
• Chemical equivalents of these diacids include esters, alkyl esters, e.g., dialkyl esters, diaryl esters, anhydrides, salts, acid chlorides, acid bromides, and the like.
• the preferred chemical equivalents comprise the dialkyl esters of the cycloaliphatic diacids, and the most preferred chemical equivalent comprises the dimethyl ester of the acid, particularly dimethyl-trans-l,4-cyclohexane-dicarboxylate.
• a preferred cycloaliphatic polyester is poly(cyclohexane-l,4- dimethylene cyclohexane-l,4-dicarboxylate) also referred to as poly(l,4- cyclohexane-dimethanol-l,4-dicar boxy late) (PCCD) which has recurring units of the formula:
• PCCD R 1 is derived from 1,4 cyclohexane dimethanol; and R is a cyclohexane ring derived from cyclohexanedicarboxylate or a chemical equivalent thereof.
• the preferred PCCD has a cis/ trans formula.
• the reaction is generally run in the presence of a suitable catalyst such as a tetrakis (2-ethyl hexyl) titanate, in a suitable amount, typically about 100 to 400 ppm of titanium based upon the final product.
• a suitable catalyst such as a tetrakis (2-ethyl hexyl) titanate
• the preferred aliphatic polyesters used in the present reinforced molding compositions have a glass transition temperature (T g ) which is above 50°C, most preferably above about 80°C.
• thermoplastic compositions which contain a polyester resin and a polycarbonate resin
• a stabilizer or quencher material In the thermoplastic compositions which contain a polyester resin and a polycarbonate resin, it is preferable to use a stabilizer or quencher material.
• Catalyst quenchers are agents which inhibit activity of any catalysts which may be present in the resins. Catalyst quenchers are described in detail in U.S. Patent 5,441,997. It is desirable to select the correct quencher to avoid color formation and loss of clarity to the polyester polycarbonate blend.
• a preferred class of stabilizers including quenchers are those which provide a transparent and colorless product. Typically, such stabilizers are used at a level of 0.001-10 weight percent and preferably at a level of from 0.005-2 weight percent.
• the preferred stabilizers include an effective amount of an acidic phosphate salt; an acid, alkyl, aryl or mixed phosphite having at least one acidic hydrogen; a Group IB or Group IIB metal phosphate salt; a phosphorus oxo acid, a metal acid pyrophosphate or a mixture thereof.
• the suitability of a particular compound for use as a stabilizer and the determination of how much is to be used as a stabilizer may be readily determined by preparing a mixture of the polyester resin component and the polycarbonate and determining the effect on melt viscosity, gas generation or color stability or the formation of interpolymer.
• the acidic phosphate salts include sodium dihydrogen phosphate, mono zinc phosphate, potassium hydrogen phosphate, calcium dihydrogen phosphate and the like.
• the phosphites may be of the formula:
• Rl, R2 and R3 are independently selected from the group consisting of hydrogen, alkyl and aryl with the proviso that at least one of Rl, R2 and R3 is hydrogen.
• the phosphate salts of a Group IB or Group IIB metal include zinc phosphate, copper phosphate and the like.
• the phosphorus oxo acids include phosphorous acid, phosphoric acid, polyphosphoric acid or hypophosphorous acid.
• the polyacid pyrophosphates may be of the formula:
• M is a metal
• x is a number ranging from 1 to 12 and y is a number ranging 1 to 12
• n is a number from 2 to 10
• z is a number from 1 to 5
• the sum of (xz) + y is equal to n + 2.
• the preferred M is an alkaline or alkaline earth metal.
• quenchers are oxo acids of phosphorous or acidic organo phosphorus compounds. Inorganic acidic phosphorus compounds may also be used as quenchers, however they may result in haze or loss of clarity. Most preferred quenchers are phosphoric or phosphorous acid.
• Cycloaliphatic polyester resins have been found to have better weatherability than polycarbonate alone. Ultraviolet light absorbers are used to improve the polycarbonate light stability. Inclusion of a light stabilizer in a cycloaliphatic polyester/ polycarbonate blend provides additional light stability for the polycarbonate resin.
• UV light absorbers useful in the present invention are those which are generally compatible with polycarbonates.
• HALS hindered amine light stabilizers
• Illustrative ultraviolet radiation absorbing compounds include 2-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N-(2-aminoethyl)-2-aminoethyl-N
• the ratio of polyester resin to ductile resin is from about 60 to 40 to about 85 to about 15. Based on the total weight of ductile resin and polyester resin, the composition preferably comprises from about 50 to about 90 weight percent polyester, more preferably from about 65 to about 85 percent polyester, and more preferably from about 70 to about 85 percent polyester.
• polycarbonate/ cycloaliphatic polyester compositions can contain up to 30% by weight of additional polymeric binder materials in the blend, preferably less than 20 percent, and more preferably less than 15 percent.
• additional ingredients may include polyalkylene phthalates or naphthanoates, polybutylene terephthalate polymers (PBT), polyethylene terephthalate polymers (PET), polypropylene terephthalate polymers (PPT), polyethylene naphthanoate polymers (PEN), polycyclohexane dimethanol terephthalates and styrene- acrylonitrile copolymers, preferably containing 25% - 35% of acrylonitrile.
• Additional, impact modifiers generally comprise an acrylic or methacrylic grafted polymer of a conjugated diene or an acrylate elastomer, alone, or copolymerized with a vinyl aromatic compound.
• these impact modifiers contain units derived from butadiene or isoprene, alone or in combination with a vinyl aromatic compound, or butyl acrylate, alone or in combination with a vinyl aromatic compound.
• Typical impact modifiers include, but are not limited to ethylene vinyl acetate, ethylene ethylacrylate copolymers, SEBS (styrene-ethylene-butylene styrene) and SBS (styrene-butadierie-styrene) block copolymers, EPDM (ethylene propylene diene monomer) and EPR (ethylene propylene rubber) copolymers, etc
• the method of blending the present compositions can be carried out by conventional techniques.
• One convenient method comprises melt blending the polyester, acrylic, impact modifier and other ingredients in powder or granular form, extruding the blend and comminuting into pellets or other suitable shapes.
• the ingredients are combined in any usual manner, e.g., by dry mixing followed by mixing in the melted state in an extruder.
• additives such as mold releases, antioxidants lubricants, nucleating agents such as talc and the like, other stabilizers including but not limited to UV stabilizers, such as benzotriazole, supplemental reinforcing fillers, and the like, flame retardants, pigments or combinations thereof may be added to the compositions of the present invention.
• Notched Izod (NI) and Unnotched Izod (UNI): This test procedure is based on the ASTM D256 method. In this case, using Izod Method E, the unnotched impact strength is obtained by testing an unnotched specimen. The results of the test is reported in terms of energy absorbed per unit of specimen width, and expressed in foot times pounds per inch (Ft.Lbs./In.). Typically the final test result is calculated as the average of test results of five test bars.
• Dynatup® (DYN TE): This test procedure is based on the ASTM D3763 method arid was performed on a Dynatup brand impact test machine. This procedure provides information on how a material behaves under multiaxial deformation conditions. The deformation applied is a high speed puncture.
• An example of a supplier of this type of testing equipment is Dynatup. Reported as test results are the so-called total energy values at various temperatures, which are expressed in foot times pounds (Ft.Lbs.). The final test result is calculated as the average of the test results of typically ten test plaques.
• the equipment used is an extrusion plastometer equipped with an automatic timer. A typical example of this equipment would be the Tinius Olson MP 987.
• the testing conditions are a melt temperature of 250°C, a total load of 5,000 gram, an orifice diameter of 0.0825 inch, and a dwell time of 5 minutes. The test result is expressed in the unit Poise.
• Flexural Modulus This test procedure for measuring stiffness is based on the ASTM D790 method. Typical test bars have the following dimensions: 1/8 inch by 1/2 inch by 2-1/2 inch. The final test result is calculated as the average of test results of five test bars. The test involves a three point loading system utilizing center loading on a simply supported beam. Instron and Zwick are typical examples of manufacturers of instruments designed to perform this type of test.
• the flexural modulus is the ratio, within the elastic limit, of stress corresponding strain and is expressed in pounds per square inch (psi).
• Examples of the invention El to E 17 as well as the control formulations C 1 to C 9 were prepared by blending all ingredients in a bucket blender until a good homogeneity of the blend was achieved. All blend formulations were extruded on a vacuum-vented 30 mm WP twin screw operated at 500 F (dye head zone - 480 F).
• Table 2 and Figure 1 elucidate the influence of different PCCD-to- PC ratios on the notched Izod values at room temperature. It can be seen that the notched Izod ductility (NI) increases with increasing PCCD content until it reaches a maximum of 24 ft. Ib./in. (E3) at roughly 75 % PCCD content. With further increasing PCCD content, the notched Izod values decrease again towards the notched Izod value of straight PCCD resin of around 12 ft. Ib./in.
• Figure 1 also demonstrates the synergistic character of this invention: with increasing PCCD content in PCCD/ PC blends the flexural modulus decreases linearly whereas the notched Izod curve exhibits a maximum at around 80 % PCCD. This behavior can be predicted by any known theory and was also not described for similar polymers in the literature.
• Lexan 100 100 80 65 50 35 20 10
• Example 1-3 The general procedure of Example 1-3 is repeated with compositional adjustments.
• the formulations used and the results obtained are set forth in Table 3 which documents experiments with a fbced PCCD/ PC ratio of 75/25 with dependence on different Lexan PC grades.
• All polycarbonate resins used are commercially available Lexan grades and differ mainly in molecular weight.
• Lexan SP is a soft- segmented Lexan 100 grade whereas the polyestercarbonate (PPC) is a BPA copolymer with isophthalic and terephthalic units described by the following structures displayed in
• Example 4-12 The general procedure of Example 4-12 is repeated making use of different core/ shell as well as reactive copolymer impact modifiers.
• the ratio of PCCD/PC was kept identical to EXAMPLES 5-12 (75/25 ratio) and the results obtained are set forth in Table 4.
• the impact modifiers used are Rohm and Haas EXL 3691, an MBS type modifier, Rohm and Haas EXL 3330, an Acrylic core shell modifier, and Elf Atochem Lotadar AX 8900 concentrate.
• Lotadar is a reactive EVA-Glycidyl Metharylate copolvmer dispersed in a polycarbonate matrix.
• the impact modifiers used do not improve the ductility further, but decrease the stiffness (FM) of the blends with the exception of Lotadar AX 8900.
• Example 13-16 The general procedure of Example 13-16 is repeated making use of different polyesters as blend components.
• the formulations used and the results obtained are set forth in Table 5.
• the polyesters used are PBCD, poly(l,4-butylene cyclohexane dicarboxylate), PCT, poly(cyclohexylene dimethylene terephthalate), PBT, PET and Hytrel 4056.
• DuPont Hytrel 4056 contains roughly 50 % of a polytetrahydrofurane soft-segment in a PBT backbone. It can clearly be demonstrated that only PCCD/ PC (E 17) blends (75/25 ratio) obtain notched Izod values of more than 18 ft. lbs./ in. All other polyesters (C5 through C8) exhibit notched Izod values that are significantly lower than E 17. It is also interesting to mention that only E 17, C 5 and C 6 are miscible and transparent blends whereas C 7 through C 9 are opaque.
• Table 6 allegorizes the transmittance of a typical PCCD/ PC blend (E 17) as a function of the light wavelength. As can be seen the blend maintains a transmittance of 80 % or more over the full range of visible light.

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• 1999
  • 1999-05-17 WO PCT/US1999/010864 patent/WO1999063002A1/en not_active Application Discontinuation
  • 1999-05-17 JP JP2000552203A patent/JP2002517538A/ja not_active Withdrawn
  • 1999-05-17 EP EP99923151A patent/EP1080152A1/de not_active Withdrawn

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