Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
  • C08L51/06—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
  • C08L67/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L77/00—Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Compositions of derivatives of such polymers

Definitions

• This invention relates to polyester polymeric materials and particularly polybutylene terephthalate having improved toughness and impact strength and to materials and methods for producing same, it also relates to polyamide resins having improved toughness and impact strength as well as materials and methods for achieving same.
• thermoplastic polyesters in engineering type applications are limited where toughness and high impact strength are required, unmodified thermoplastic polyesters typically exhibit room temperature impact strength of 1 ft-lb/inch of notch or less on the izod scale of impact strength.
• SUBSTITUTE SHEET the rubber-like or elastomeric materials with sites that enable the polyester or polycarbonate resins to adhere to the elastomeric materials.
• the Cope patent does not teach or suggest the components of the additive employed in the practice of the invention described and claimed herein, as will hereinafter appear.
• Epstein patent is somewhat confusing in that it seeks to cover -the waterfront by listing an endless number of materials and combinations thereof for use as additives to improve the toughness and impact strength of polyester and polycarbonate resins.
• stress is placed on the particle size and tensile modulus of the copolymer additive.
• Epstein contemplates the use of ethylene-propylene copolymers and ethylene-propylene- polyene terpolymers from amongst the large number of other varieties of materials and the use of a, ⁇ ethylenically unsaturated carboxylic and dicarboxylic acids and anhydrides as modifying agents to provide sites which adhere to the matrix resin, the Epstein patent does not recognize the concepts of the invention described and claimed as will hereinafter be pointed out.
• compositions comprising 60-90 percent by weight of a matrix resin in the form of a polyester blended with 10-40 percent by weight of an unsaturated rubber formed by copolymerization pf ethylene - one or more mono-olefins and one or more polyenes in which the backbone unsaturated rubber component has been modified with an ester of an a, ⁇ -unsaturated acid having an epoxide functionality on the alkoxy portion such as the ester derived from methacrylic acid and an epoxy alcohol and which attaches to the backbone rubber chiefly by way of a grafting reaction with little if any cross-linking reaction.
• Polyesters and their method of manufacture are well known to the skilled in the art and are readily available in commerce. While the invention will hereinafter be described in greater detail with reference to polybutylene terephthalate as a preferred polyester such as marketed by the General Electric Plastics Company under the trademark Valox 310 and Valox 315, others of the polyesters such as described in the above-mentioned Epstein U.S. patent No. 4,172,859 can be used in the practice of this invention for their improvement in toughness and impact strength.
• the backbone rubber is formed by interpolymerization of monomers of ethylene, one or more higher mono-olefins having from 3-16 carbon atoms, preferably propylene, plus one or more polyenes.
• the polyene monomer containing a plurality of carbon-to-carbon double bonds may be selected from those disclosed in the prior art for use as third monomers in the preparation of ethylene-mono-olefin-polyene terpolymers, including open chain polyunsaturated hydrocarbons containing 4-20 carbon atoms, such as 1,4-hexadiene, monocyclic polyenes and polycyclic polyenes.
• the polyunsaturated bridged ring hydrocarbons or halogenated bridged ring hydrocarbons are preferred.
• bridged ring hydrocarbons examples include the polyunsaturated derivatives of bicyclo (2,2,1) heptane wherein at least one double bond is present in one of the bridged rings, such as dicyclopentadiene, bicyclo(2,2,l)hepta-2,5-diene, the alkylidene nobornenes, and especially the 5-alkylidene-2-norbornenes wherein the alkylidene group contains 1-20 carbon atoms and preferably 1-8 carbon atoms, the alkenyl norbornenes, and especially the 5-alkenyl-2-norbornenes wherein the alkenyl group contains about 3-20 carbon atoms and preferably 3-10 carbon atoms.
• bridged ring hydrocarbons include polyunsaturated derivatives of bicyclo(2,2,2) octane as represented by bicyclo(3,2,1) octane, polyunsaturated derivatives of bicyclo(3,3,1) nonane, and polyunsaturated derivatives of bicyclo(3,3,2) nonane.
• bridged ring compounds include 5-methylene-2-norbornene, 5-ethylidene- 2-nor ornene, 5-n-propylidene-2-norbornene, 5-isobutylidene-2-norbornene, 5-n-butylidene-2-norbornene, 5-isobutylidene-2-norbornene, dicyclopentadienes: the methyl butenyl norbornenes such as 5-(2-methyl-2-butenyl)- 2-norbornene or 5-(3-methyl-2-butenyl)-norbornene, and 5-(3,5-dimethyl-4-hexenyl)-2-norbornene.
• the elastomer prepared from 5-ethylidene-2-norbornene is much preferred as it has outstanding properties and produces many unusual and unexpected results.
• the backbone rubber may contain chemically bound therein molar ratios of ethylene to propylene or other
• CJ-,-Cl,_- mono-olefin varying between 95:10 to 5:90 .
• ethylene:propylene and preferably between 70:30 to 55:45 ethylene:propylene.
• the polyene or substituted polyene may be chemically bound therein in an amount of 0.1 to 10 mol percent, and preferably 0.3 to 1 mol percent, or in an amount to provide an actual unsaturation level of 2-10 double bonds per 1,000 carbon atoms in the polymer chain.
• the interpolymerization reaction is carried out in the presence of a catalyst in a solvent medium.
• the polymerization solvent may be any suitable inert organic solvent that is liquid under reaction conditions.
• hydrocarbon solvents examples include straight chain paraffins having from 5-8 carbon atoms, with best results often being secured by the use of - hexane; - aromatic hydrocarbons and preferably an aromatic hydrocarbon having a single benzene nucleus, such as benzene, toluene and the like; and saturated cyclic hydrocarbons having boiling point ranges approximating those of the straight chain paraffin hydrocarbons and aromatic hydrocarbons described above, and preferably saturated cyclic hydrocarbons having 5-6 carbon atoms in the ring nucleus.
• the solvent selected may be a mixture of one or more of the foregoing hydrocarbons and preferably a mixture of aliphatic and naphthenic hydrocarbons having approximately the same boiling range as normal hexane. It is desirable that the solvent be dry and free of substances that will interfere with the Ziegler type catalyst used in the polymerization reaction.
• the interpolymerization is carried out in the presence of a ziegler catalyst of the type well known to the prior art.
• ziegler type catalysts are disclosed in a large number of patents, such as U.S. patents No. 2,933,480, No. 3,093,620, No. 3,093,621, No. 3,211,709 and No. 3,113,115. Examples of Ziegler catalysts include
• SUBSTITUTE SHEET metal organic coordination catalysts prepared by contacting a compound of a heavy metal of the group IV-a, V-a, Vl-a and Vll-a of the Mendeleeff periodic system of elements, such as titanium, vanadium and chromium halides with an organo-metallic compound of a metal of groups I, II or III of the Mendeleeff periodic system which contains at least one carbon-metal bond, such as trialkyl aliminum, and allyl aluminum halides in which the alkyl groups contain fro 1-20 and preferably 1-4 carbon atoms.
• the preferred Ziegler catalyst for interpolymerization is prepared from a vanadium compound and an alkyl aluminum halide.
• Suitable vanadium compounds include vanadium trichloride, vanadium tetrachloride, vanadium oxychloride, vanadium acetyl acetonate, etc.
• Activators which are especially preferred include alkyl aluminum chlorides of 3,113,115, having the general formula R,AlCl- and R-AlCl and the corresponding sesquichlorides of the general formula R-A1.-C1,, in which .R is methyl, ethyl, propyl, butyl or isobutyl.
• the aluminum to vanadium mol ratio of the aluminum and vanadium compounds may be within the range of 5/1 to 200/1 and preferably within the range of 15/1 to 60/1, with best results being secured in the ratio of 40 aluminum to 1 vanadium.
• These same ratios apply with respect to corresponding compounds of others of the heavy metals substituted for the vanadium compound and the organo-metallic compounds of groups I, II and III for the aluminum compounds.
• a catalyst prepared from alkyl aluminum sesquichloride, such as the methyl or ethyl aluminum sesquichloride and vanadium oxychloride is preferred in the ratio of 1 mole vanadium oxychloride per 5-300 moles of aluminum and more preferably 15-60 moles of aluminum, with 40 moles of aluminum per mole of vanadium yielding the best results.
• the polymerization is preferably carried out on a continuous basis in a reaction vessel closed to the outside atmosphere, which is provided with an agitator, cooling means and conduit means for continuously supplying the ingredients of the reaction including monomer, catalyst and accelerators and conduit means for continuously withdrawing solution containing elastomer, and the catalyst is killed by the addition of a catalyst deactivator.
• EPDM polymers The preparation of EPDM polymers is well known and is fully described in such patents as U.S. patents No. 2,933,480, No. 3,093,621, No. 3,211,709, No. 3,646,168, NO. 3,709,519, No. 3,884,993, No. 3,894,999 and No. 4,059,654, amongst many others.
• R* is an organic group having an epoxide functionality and R is hydrogen, methyl, ethyl, propyl or other alkyl, aralkyl, cyclic, or aromatic grou'p.
• substituentyl acrylate glycidyl 2-ethylacrylate
• glycidyl 2-propylacrylate glycidyl 2-propylacrylate and the like.
• the catalyst is one that favors grafting reaction over a cross-linking reaction under the reaction conditions to combine the epoxide modifying agent with the unsaturated backbone rubber.
• a free radicle initiator such as a dialkyl peroxide.
• use can be made of the catalyst in an amount within the range of 1-5 parts per 100 parts by weight of the unsaturated rubber, and preferably in an amount within the range of 1-2 percent by weight.
• the level of graft of the epoxy modifying agent onto the unsaturated backbone rubber is somewhat dependent on the amount of unsaturation in the backbone rubber. It is desirable to make use of an ethylene, mono-olefin.
• SUBSTITUTE SHEET polyene backbone rubber having at least two unsaturated carbon-to-carbon linkages per 1000 carbon atoms and little additional benefit is derived from the use of an unsaturated backbone rubber having more than 20 carbon-to-carbon double bonds per 1000 carbon atoms.
• an unsaturated rubber having from 4-10 carbon-to-carbon double bonds per 1000 carbon atoms or which provide for a level of graft within the range of 1-10 percent and preferably 1.5-4 percent by weight of the rubber.
• the grafting reaction is carried out in solvent solution with the unsaturated rubber present in a concentration which may range from 10-30 percent by weight,with constant stirring, at an elevated temperature within the range of 125-200°C for a time ranging from 1/2-2 hours.
• the reaction condition can be varied depending somewhat upon the type and amount of catalyst and temperature conditions, as is well known to the skilled in the art.
• RSV Reduced solution viscosity
• Melt flow index was measured according to ASTM D1238, using condition F.
• SUBSTITUTE SHEET Gel content is the amount of sample, expressed as a percent, which failed to dissolve in toluene after shaking 4 hours at room temperature. One gram of sample was added to 100 milliliters of toluene. Samples containing less than 5% gel are considered gel free.
• Tensile strength was measured according to ASTM D638. Blends were prepared using three extrusions through a Killion extruder having an L/D ratio of 20/1. zone temperatures were 450°F, and a die temperature of 425°F was used. The air cooled strands were chopped into pellets. These were molded into test specimens in a plunger type injection molder with a cavity temperature of 540°F and a mold temperature of 200°F. The specimens were stored in moisture proof polyethylene bags at least 16 hours before testing.
• the starting polymer is a 2.3 RSV EPDM having an ethylene/propylene molar ratio of 65/35 and having as the ter onomer 5-ethylidene-2-norbornene, at a level of seven weight percent.
• the starting polymer is a 2.2 RSV EPDM having an ethylene/propylene molar ratio of about 65/35 and having as the termonomer ethylidene norbornene at a level of four weight percent.
• This starting rubber was grafted in the manner of Example 1. Analysis of a purified sample of the product indicated 1.6 weight percent bound GMA. The product had an RSV of 2.1 and a melt flow of 5.2 g/10 minutes. The product was gel free.
• EXAMPLE 3 The starting polymer is a 2.7 RSV EPDM having an ethylene/propylene molar ratio of about 65/35 and having ethylidene norbornene as the termonomer at a level of four weight percent. This starting rubber was grafted in the manner of Example 1. Analysis of a purified sample of the product indicated 1.4 weight percent bound GMA. The product had an RSV of 2.7 and a melt flow of 0.6 g/10 minutes. The product was gel free.
• EXAMPLE 4 The starting polymer is a 2.8 RSV ethylene propylene (EPM) rubber having an ethylene/propylene molar ratio of about 60/40 and containing no termonomer. This starting rubber was grafted in the manner of Example 1. Analysis of a purified sample of the product indicated 0.4 weight percent bound GMA. The product has an RSV of 2.7 and a melt flow of 1.3 g/10 minutes. The product was gel free.
• EPM ethylene propylene
• SUBSTITUTE SHEET The following are examples of blends made of the described modified rubbers with polybutylene terephthalate (PBT) thermoplastic polyester, marketed under the trade name Valox 315 by the General Electric plastics Company.
• PBT polybutylene terephthalate
• Example 5 is an 80/20 blend of Valox 315 polybutylene terephthalate (PBT) thermoplastic polyester and the product of Example 1.
• valox 315 is a product of the General Electric Plastics Company.
• Example 6 is an 80/20 blend of Valox 315 and the product of Example 2.
• Example 7 is an 80/20 blend of Valox 315 and the product of Example 3.
• Example 8 is an 80/20 blend of Valox 315 and the product ** of Example 4. control I
• Control I is unmodified Valox 315.
• Control II is unmodified Valox 315.
• Control II is an 80/20 blend of Valox 315 and the starting rubber of Example 1. Table I summarizes the properties of the polyester blends and controls.
• the base rubber having a diene content of seven weight percent provided a degree of grafting of 2.6%
• the base rubbers having a diene content of four percent provided a degree of grafting of about 1.5%
• the base rubber containing no diene provided a degree of grafting of only 0.4%.
• the significance of this is demonstrated by the fact that the modifier of. Example 8, having the lowest degree of grafting, is the least effective of the grafted modifiers. It was observed that blends of ungrafted EPDM and polyester do not only show little improvement in impact strength, but also exhibit visual incompatibility in the form of a "plywood" morphology. This is especially true when molded specimens are flexed or fractured as in the Izod impact test. Blends of polyester and the GMA grafted EPDM's described here showed no evidence of delamination, but rather exhibited complete visual homegeneity.
• the grafting of the rubber with glycidyl methacrylate provides compatibility between the grafted rubber and polyester.
• the mode of action may be a purely physical attraction between polar groups in the polyester and the GMA groups attached to the EPDM backbone rubber.
• a covalent bond forming reaction between the polyester and the rubber grafted with the glycidyl methacrylate, as envisioned in Equation 1 may be the explanation, in which
• SUBSTITUTE SHEET the OH groups of the polyester are provided either by hydroxyl or carboxyl groups which are the normal end groups for polyester. Equation 1
• the base rubber is that of Example 1. This base rubber was reacted with 10 parts glycidyl acrylate and 2 parts dicumyl peroxide per 100 parts rubber in the manne* described in Example 1. The product was not examined for degree of grafting. The RSV of the product could not be measured because it was insoluble. The melt flow of the product was 0 g/10 minutes. The product contained 64.3% gel. These results are attributed to cross-linking of the rubber during the graft reaction.
• EXAMPLE 10 The base rubber is that of Example 4. This base rubber was reacted with 10 parts glycidyl acrylate and 2 parts dicumyl peroxide per 100 parts rubber in the manner of Example 1. The product had an RSV of 2.6 and a melt flow of 1.8. The product was gel free. This implies that, in the case of glycidyl acrylate, the crosslinking which accompanies grafting may be controlled by adjusting the level of unsaturation in the base rubber.
• Example 11 is an 80/20 blend of Valox 315 and the product of Example 9.
• Example 12 is an 80/20 blend of Valox 315 and the product of Example 10. TABLE II
• Example 13 The base rubber of Example 1 was reacted with 5 parts GMA and 2 parts dicumyl peroxide per 100 parts rubber in the manner of Example 1. Analysis of a purified sample of the product indicated 2.8 percent bound GMA. The gel-free product had an RSV of 2.4 and a melt flow of 0.7 g/10 minutes. The maintenance of a high degree of grafting in comparison with the 10 part monomer charge is taken to indicate that, as regards the graft reaction, the monomer is in excess.
• Example 14 The base rubber of Example 1 was reacted with 5 parts glycidyl acrylate and 2 parts dicumyl peroxide per 100 parts rubber in the manner of Example 1. The product was analyzed to contain 3.4% bound glycidyl acrylate. No RSV could be obtained because the sample was insoluble. The product had a melt flow of 0 g/10 minutes. The product had a gel content of 48.7%.
• EXAMPLE 15 The base rubber of Example 1 was grafted with 5 parts glycidyl acrylate, 5 parts methyl methacrylate, and 2 parts dicumyl peroxide per 100 parts rubber in the manner of Example 1. Analysis of a purified sample of the product indicated a degree of grafting of 2.0% GA. No analysis for bound methyl methacrylate was made. The product had an RSV of 2.5 and a melt flow of 0.5 g/10 minutes. The product was gel free. EXAMPLE 16 The base rubber of Example 1 was reacted with 10 parts methyl methacrylate and 2 parts dicumyl peroxide in the manner of Example 1. The product was not analyzed for degree of grafting. The product had an RSV of 2.4 and a melt flow of 2.4 g/10 minutes. The product was gel free.
• Example 17 is an 80/20 blend of Valox 315 and the product of Example 13.
• Example 18 is an 80/20 blend of Valox 315 and the product of Example 14.
• Example 19 is an 80/20 blend of Valox 315 and the product of Example 15.
• Example 20 is ⁇ an 80/20 blend of Valox 315 and the product of Example 16.
• GMA glycidyl methacrylate
• GA glycidyl acrylate
• MMA methyl methacrylate
• Example 15 (blend Example 19) using glycidyl acrylate as the grafting monomer.
• Example 14 (blend Example 18) still did not perform equal
• this effect may be a general one. That is it may extend to the cases of other monomers such as most acrylates, vinyl monomers, and acrylonitrile, which promote cross-linking of EPDM during grafting possibly by reason of the mechanism of graft chain • termination, incorporation of graft comonomers which alter the termination mechanism may be used to eliminate undesirable cross-linking which often renders the product useless in the application d-esired.
• monomers such as most acrylates, vinyl monomers, and acrylonitrile
• EXAMPLE 21 The starting polymer is that of Example 1.
• the modifier was prepared in the manner of Example 1. Analysis of a purified sample of the product indicated 2.8% bound GMA. The product had an RSV of 2.4 and melt flow of 0.9 g/10 minutes. The product was gel free.
• Example 22 is an 80/20 blend of Nylon 6 and the product of Example 21. Control III
• Control III is the unmodified Nylon 6 of Example 22. It is a polycaprolactam having a degree of polymerization of about 200 and a formic acid solution viscosity of 70.
• the melt flow of the Nylon 6 under Condition L of ASTM D1238 was 14 g/10 minutes.
• Example 23 is an 75/25 blend of nylon of Control III and the product of Example 21.

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• 1986
  • 1986-01-08 WO PCT/US1986/000014 patent/WO1986004076A1/en not_active Application Discontinuation
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