DK155744B - THERMOPLASTIC POLYMER MIXTURE BASED ON A POLYCARBONATE RESIN, A GRAINED COPOLYMER AND A COPOLYMER - Google Patents

Description

DK 155744B

The present invention relates to a thermoplastic polymer blend based on a polycarbonate resin, an inoculated copolymer and a copolymer, which polymer blend has excellent physical properties such as impact resistance and heat resistance, as well as improved weld strength.

Polycarbonate resins have excellent physical properties, especially high impact resistance and heat resistance, and they are known as engineering plastics. It is also known to mix different resins into polycarbonate resins to improve their physical properties with respect to their less good properties. For example, incorporation of ABS resins (acrylonitrile-butadiene styrene copolymer), MBS resins (methyl methacrylate-butadiene styrene copolymer), and ABSM resins (acrylonitrile-butadiene-styrene-methyl methacrylate copolymer) into polycarbonate copolymer copolymer copolymer their formability and reduction of the thickness's dependence on the thickness (cf. Japanese Patent Specification Nos. 15225/1963, 71/64, 11496/67 and 11142/76). Furthermore, for example, incorporation of AES resins (acrylonitrile-ethylene / propylene rubber styrene copolymer) into polycarbonate resins is effective in improving weather and wind resistance and stain resistance (cf. Japanese Publication No. 48547/1973).

In injection molding, which is the most common casting method, it is necessary to change the number of inlet openings and the flow state of the resin depending on the shape and size of the molded product. Thus, crosses are inevitably formed in the resin flowing in different directions, thereby forming a weld portion. The weld portion of a molded product made from a conventional thermoplastic resin composition comprising a polycarbonate resin in which a rubber modified copolymer is incorporated usually has an insufficient strength and this is a major drawback for practical purposes.

It has now been found that by incorporating an olefin copolymer containing an epoxy group into a thermoplastic resin composition comprising a polycarbonate resin and a rubber modified copolymer DK 155744 B '2 as well as an additional copolymer, a resinous composition having excellent physical properties such as impact strength is obtained. and heat resistance, as well as with improved welding strength.

Accordingly, according to the present invention, there is provided a thermoplastic polymer blend having improved welding strength, the polymer blend being characterized by comprising a) a polycarbonate resin, b-Ί) an inoculated copolymer prepared by graft polymerization of at least two monomers selected from aromatic compounds. vinyl compounds, vinyl cyanides and alkyl esters of unsaturated carboxylic acids on conjugated diene gums or ethylene-propylene gums, wherein the weight ratio of rubber to monomers is between 5:95 and 70:30, b-2) a copolymer of at least two monomers selected from aromatic vinyl compounds, vinyl cyanides and alkyl esters of unsaturated carboxylic acids, wherein b-1) represents 10-100% of b-1) + b-2) and b-2) represents 90-0% of b-1) + b-2), 15 and c) an olefin copolymer containing an epoxy group.

Danish Patent Application No. 5851/68 and U.S. Patent No. 3,954,905 disclose polymer blends comprising a polycarbonate resin, an inoculated copolymer and an additional copolymer. These known polymer blends do not contain olefin copolymers containing epoxy groups, and the polymer blend of the invention which, as stated, contains an olefin copolymer containing an epoxy group, has significantly improved weld strength compared to the known polymer blends while maintaining high heat distortion temperature and good impact strength.

For example, as polycarbonate resin, which is component a), can be used aliphatic polycarbonates, aromatic polycarbonates, aliphatic-aromatic polycarbonates, etc. Polymers and copolymers of bisphenols such as bis (4-hydroxyphenyl) alkanes, bis (4-hydroxyphenyl) are usually used. ethers, bis (4-hydroxyphenyl) sulfones, bis (4- hydroxyphenyl) sulfides and bis (4-hydroxyphenyl) sulfoxides and / or halogenated bisphenols. Typical examples of polycarbonate resins and their preparation are described in various textbooks and reference works, including the Encyclopedia of Polymer Science and Technology, 10, 1969, pp. 710-764.

DK 155744 B

3

The rubber-modified copolymer constituting component b) is obtained by polymerizing at least two kinds of monomers selected from aromatic vinyl compounds, vinyl cyanides and alkyl esters of unsaturated carboxylic acids in the presence of gums. The resulting product 5 comprises b-1) a copolymer comprising units of the rubber and units of the monomers which are graft polymerized thereon (hereinafter referred to as "grafted copolymer") and usually b-2) a copolymer comprising units of the monomers (hereinafter referred to as "copolymer"). Alternatively, the graft copolymer b-1) and polymer b-2) can be prepared separately and combined to form a uniform composition which can be used as component b). Usually, the rubber-modified copolymer b) comprises the grafted copolymer b-1) and the copolymer b-2) in amounts of 10-100% by weight and 90-0% by weight, respectively, of the weight of rubber-modified copolymer b). When the content of the graft copolymer (b-1) is less than 10% by weight, the final composition will have an insufficient impact strength.

The weight ratio of the rubber to the monomers of the graft copolymer b-1) is 5: 95-70: 30. The composition of the monomers may comprise, for example, 20 or more aromatic vinyl compounds in an amount of 50-80% by weight and one or more vinyl cyanides and / or an alkyl ester of one or more unsaturated carboxylic acids in an amount of 50-20% by weight.

There is no particular restriction on the particle size of the graft copolymer (b-1), and it can usually be 0.05-5 µm, especially 0.1-0.5 µm.

For example, the composition of the monomers in the copolymer b-2) may comprise one or more aromatic vinyl compounds in an amount of 50-90% by weight and one or more vinyl cyanides and / or an alkyl ester of one or more unsaturated carboxylic acids in an amount of 50-10% by weight. 30 percent. There is no particular limitation on the logarithmic viscosity number of the copolymer b-2) and it can usually be 0.60-1.50 dl / g (determined in dimethylformamide at 30 ° C).

Examples of the gum for the graft copolymer b-1) are polybutadiene, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, ethylene / 4 propylene copolymer, ethylene / propylene / unconjugated diene copolymer (e.g. dicyclopentadiene, ethylidene norbornene, 1,4-cyclohexadiene, 1,4-cyclo-heptadiene, 1,5-cyclooctadiene), ethylene / vinyl acetate copolymer, chlorinated polyethylene, polyalkyl acrylate, etc. As for the ethylene / propylene copolymer or ethylene / propylene / unconjugated diene copolymer, the molar ratio of ethylene to propylene may be 5: 1-1: 3. The content of unconjugated diene in the ethylene / propylene / unconjugated diene copolymer is preferably 2-50 expressed in iodine number. Examples of aromatic vinyl compounds are styrene, α-methylstyrene, methyl-α-methylstyrene, vinyl toluene, monochlorostyrene, etc. Examples of vinyl cyanides are acrylonitrile, methacrylonitrile, etc. Examples of the alkyl ester of one or more unsaturated carboxylic acids are alkyl acrylates (e.g., methyl acrylate, ethyl acrylate, butyl acrylate), alkyl methacrylates (e.g., methyl methacrylate, ethyl methacrylate, butyl methacrylate), hydroxyalkyl acrylates (e.g., hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyalkylmethyl acrylate,

For the preparation of the rubber modified copolymer b), any conventional polymerization process such as emulsion polymerization, suspension polymerization, bulk polymerization, solution polymerization, emulsion / suspension polymerization and bulk / suspension polymerization can be used.

In the thermoplastic polymer blend of the invention, the weight ratio of the polycarbonate resin a) to the rubber-modified copolymer b) may be 10: 90-90: 10. When the content of the polycarbonate resin (a) is less than the lower limit, the resistance to heat and the weld strength are substantially reduced. When the content is greater than the upper limit, the formability is noticeably reduced. In addition, the appearance deteriorates to such an extent that the composition is no longer suitable for practical purposes.

The epoxy group-containing olefin copolymer c) containing an epoxy group is a copolymer of at least one unsaturated epoxy compound and at least one olefin with or without at least one ethylenically unsaturated compound. While there is no particular restriction on the composition of these monomers, the content of the 35 or unsaturated epoxy compounds is preferred to be 0.05-95% by weight.

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5

As the unsaturated epoxy compound (s), compounds can be used with an unsaturated group copolymerizable with an olefin and an ethylenically unsaturated compound as well as an epoxy group in the molecule. For example, unsaturated glycidyl esters, unsaturated glycidyl ethers, epoxy alkenes, p-glycidyl styrenes may be used, etc. The compounds shown below may also be used:

II

R-C-O-CH - CH-CH-I

\ /

ISLAND

R-X-CH-CH-CH-II

\ /

ISLAND

R

R-C-CH 2 III

wherein R represents a hydrocarbon having from 2 to 18 carbon atoms and with ethylenic unsaturation, R 'represents hydrogen or methyl, and X represents -CH 2 O-, or The following compounds are used: glycidyl acrylate, glycidyl methacrylate, glycidyl aconate , butene carboxylates, allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-β-glycidyl ether, 3,4-epoxybutene, 3,4-epoxy-3-methyl-1-butene, 3,4-epoxy-1-pentene, 3 , 4-epoxy-3-methylpentene, 5,6-epo-xy-1-hexene, vinylcyclohexene monoxide, p-glycidylstyrene, etc.

Examples of olefins are ethylene, propylene, butene-1,4-methylpentene-1, etc.

The ethylenically unsaturated compounds may be, for example, olefins, vinyl esters with a saturated C 1 -C 8 carboxylic acid moiety, acrylic and methacrylic esters with a saturated C 1 -C 8 alcohol moiety, maleic acid esters with a saturated C , etc. These ethylenically unsaturated compounds may be copolymerized with the unsaturated epoxy compounds and olefins in an amount of not more than 50% by weight, in particular 0.1-45% by weight of the total weight of the monomers to be copolymerized.

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6

The epoxy group-containing olefin copolymer c) can be prepared by various processes, a typical example of which involves contacting an unsaturated epoxy compound and an olefin with or without an ethylenically unsaturated compound at a radical-generating agent at a temperature of 40-300 ° C. pressure of 506-405000 kPa.

Another typical example comprises irradiation with gamma rays of a mixture of polypropylene and an unsaturated epoxy compound under greatly reduced pressure.

There is no particular restriction on the amount of epoxy group-containing olefin copolymer c) to be incorporated, and it can usually be present in an amount of 0.1-40 parts by weight per minute. 100 parts by weight of the total weight of the polycarbonate resin a) and the rubber modified copolymer b). When the quantity is less than the lower limit, satisfactory dispersibility cannot be guaranteed.

When the amount is more than the upper limit, there is a tendency to form phase separation in the molded product. For the impact strength, weld strength and processability of the thermoplastic resin composition, an amount of 0.5-10 parts by weight is particularly preferred.

For the preparation of the thermoplastic polymer blend according to the invention, these essential ingredients can be mixed together in any order. For example, they can all be mixed together. Furthermore, for example, the two of them may first be mixed together, followed by incorporation of the remaining component into the resulting mixture. The mixture can be obtained using any conventional mixer such as a Banbury mixer, a monoaxial extruder or a biaxial extruder. If desired, any other resin such as a polyolefin resin (e.g., polyethylene, polypropylene, ethylene / propylene copolymer) and / or any additives such as dyes, pigments, stabilizers, pesticides, antistatic agents, absorbent agents, ultraviolet rays, fire retardants, lubricants and fillers are incorporated into the thermoplastic polymer blend.

The invention is further illustrated by the following examples.

DK 155744B

7 EXAMPLES Ί-9 AND COMPARATIVE EXAMPLE 1-7 According to the specification shown in Tables 1 or 2, the polycarbonate resin a), the grafted polymer b-1) and / or the copolymer b-2) and optionally the epoxy group-containing olefin copolymer c) were mixed. or polyethylene together to give a thermoplastic polymer blend whose physical properties are shown in Tables 1 or 2.

Of the resins or polymers used, the polycarbonate resin a) and the polyethylene resin were commercially available. The rubber modified copolymer b) and the epoxy group-containing olefin copolymer 10 c) were prepared as described below.

Polycarbonate Resin (a): "Panlite L-1250W", manufactured by Teijin Chemical, has the following structural formula: CH-O

Rubber Modified Copolymer b) (# 1): 15 Grafted Copolymer (b-1)

Polybutadiene (gel content 90%) (50 parts by weight of solid), 0.5 parts by weight of cesium persulfate, 0.5 parts by weight of potassium olefinate and 0.5 parts by weight of dodecyl mercaptan were mixed together, to the mixture 36 parts by weight of styrene and 14 parts by weight of acrylonitrile were added. performed at 20 ° C for 3 hours followed by ripening for 1 hour. The reaction mixture was subjected to salting, dehydration and drying to give a graft copolymer with a particle size of 0.3-0.4 µm.

Copolymer b-2)

To a mixture of 70 parts by weight of styrene and 30 parts of acrylonitrile, 25 0.1 parts by weight of t-dodecyl mercaptan were added and the resulting mixture was

DK 155744B

8 subjected to prepolymerization in bulk at 90 ° C for 3 hours. 210 parts by weight of water, 1.0 parts by weight of methyl cellulose and 0.3 parts by weight of benzoyl peroxide were added. The resulting aqueous dispersion was heated from 30 ° C to 90 ° C and polymerization in the dispersed state was carried out for 5 hours. Removal of the water gave a copolymer with a logarithmic viscosity number of 0.50 dl / g (determined in dimethylformamide at 30 ° C).

Rubber modified copolymer (b) (No 2):

Graft copolymer (b-1)

Ethylene / propylene / u conjugated diene copolymer (EPDM) (iodine number: 8.5; 10 Mooney viscosity: 61; propylene content: 43% by weight; unconjugated diene component: ethylidene norbornene) (150 parts by weight) was dissolved in a mixture of 3000 parts by weight of n hexane and 1500 parts by weight of dichloroethylene.

300 parts by weight of styrene, 150 parts by weight of acrylonitrile and 11 parts by weight of benzoyl peroxide were added and the polymerization was carried out at 65 ° C for 10 hours under a nitrogen atmosphere. The reaction mixture was contacted with a large excess of methanol. The precipitate was collected by filtration and dried to give a graft copolymer (gum content about 24% by weight).

Copolymer (b-2) 20 To a mixture of 70 parts by weight of styrene and 30 parts by weight of acrylonitrile was added 0.1 parts by weight of t-dodecylmercaptan and the resulting mixture was subjected to prepolymerization in bulk at 90 ° C for 3 hours. 210 parts by weight of water, 1.0 parts by weight of methyl cellulose and 0.3 parts by weight of benzoyl peroxide were added. The resulting aqueous dispersion was heated from 30 ° C to 90 ° C and polymerization in the dispersion state was carried out for 10 hours. Removal of the water gave a copolymer with a logarithmic viscosity number of 0.50 dl / g (determined in dimethylformamide at 30 ° C).

Epoxy group-containing olefin copolymer c): 7

Compressed ethylene (2000 kg / cm), glycidyl methacrylate and vinyl acetate 30 were placed in an autoclave together with di-t-butyl peroxide as the catalyst.

DK 155744B

g of sator and the mixture was stirred at 150-300 ° C for several minutes, undergoing bulk polymerization. The reaction mixture is passed through a separator to collect an epoxy group-containing olefin copolymer.

Polyethylene Resin: "Sumikathen Hard 2703" manufactured by Sumitomo Chemical.

The welding strength was determined as follows:

A molten resin (200 ° C) was injected through two inlet apertures (2.5 x 2.0 mm each) with a distance between the inlet apertures of 10 100 mm to produce a specimen 150 mm long, 150 mm wide and 3 mm high. The sample was placed on a cylinder with an inner diameter of 120 mm, an outer diameter of 126 mm and a height of 80 mm. A 1 kg steel ball was dropped onto the central part of the specimen in a room whose temperature was maintained at 15 -30 ° C and the maximum energy (kp.cm) which did not break the specimen was measured.

Example 10

DK 155744B

Table 1

Test # 1 2 3 4 5 5 -

composition:

Polycarbonate resin a) 40 50 50 60 70 C parts by weight)

Inoculated copolymer b-1) 25 30 15 20 10 10 (parts by weight)

Copolymer b-2) 35 20 35 20 20 (parts by weight)

Epoxy group-containing olefin copolymer c) (parts by weight) E-GMA-VA 1) 3-3-2 E-GMA2) - 2 - 1.5 -

Polyethylene (parts by weight) _____

Welding strength (DuPont impact strength at weld seam) 20 (-30 ° C) (kp.cm)> 200> 200 190> 200 180 Shear impact strength according to Izod's test (20 ° C) (kg.cm/cm2) 48.6 56, 6 48.5 52.0 51.0

Thermal formation temperature (1820 kN / m2, without curing) (° C) 100.5 105.0 106.0 108.7 112.3

Processability (Koka-type flow tester, 230 ° C, 60 kg / cm2) (ml / min) 0.51 0.50 0.55 0.48 0.42 4 30 Bending model, x 10 (kg / cm2) 2, 0 2.1 2.2 2.15 2.25

Comparative Example 11

DK 155744B

Test No. 12 3 5 Composition:

Polycarbonate resin (a) (parts by weight) 50 60 50

Grafted copolymer b-1) 30 20 30 (parts by weight) 10 Copolymer b-2) 20 20 20 (parts by weight)

Epoxy group-containing olefin copolymer c) (parts by weight) E-GMA-VA 1) - 15 E-GMA 2) -

Polyethylene (parts by weight) 3

Welding strength (DuPont impact strength at weld seam (-30 ° C) (b.cm) 20 25 45 20 Shear impact strength according to Izod's test (1820 kN / m ^), without curing) (° C) 55.0 56.3 53, 2

Heat deformation temperature (1829. kN / m 2, without curing (° C) 105.2 106.5 105.8

Processability (Koka-type flow tester, 230 ° C, 60 kg / cm 2) (ml / min) 0.50 0.56 0.58 Bending module, x 10 2 (kg / cm 2) 2.1 2.2 2, Note: 1) Ethylene / glycidylmethacrylate / vinyl acetate copolymer (90: 7: 3), 2) Ethylene / glycidylmethacrylate copolymer (90:10).

12

DK 1557 44 B

Table 2 Example

Test No. 6 7 8 9 5 -

composition:

Polycarbonate resin a) (parts by weight) 45 55 60 70

Graft copolymer b-1) 25 25 15 15 10 (parts by weight)

Copolymer b-2) 30 20 25 15 (parts by weight)

Epoxy group-containing olefin copolymer c) (parts by weight) E-GMA-VA 1) 2.0 0 2.5 2.0 E-GMA 2) 0 2.0 0 0

Polyethylene (parts by weight) -

Welding strength (DuPont impact strength at weld seam) (-30 ° C) (b.cm)> 200> 200> 200> 190 Sheathing impact according to Izod's test (20 ° C) (kg.cm/cm2) 51.5 58.5 48.0 50.0

Heat deformation temperature (1820 kN / m2), without curing (° C) 100.5 103.7 105.5 108.6

Processability (Koka-type flow tester, 230 ° C, 60 kg / cm2) (ml / min) 0.50 0.48 0.47 0.43 4 30 Bending module, x 10 (kg / cm2) 2.1 2, 0 2.2 2.25

Note: 1) and 2): as in Table 1.

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Comparative Example 13

Test No. 4 5 6 7 5 Composition:

Polycarbonate resin (a) (parts by weight) 60 95 55 55

Inoculated copolymer b-1) 15 5 3 25 (parts by weight) 10 Copolymer b-2) 25 0 42 20 (parts by weight)

Epoxy group-containing olefin copolymer c) (parts by weight) E-GMA-VA 1) 0 0 3.0 0 15 E-GMA 2) 0 0 0 0

Polyethylene (parts by weight) - - - 3.0

Welding strength (DuPont impact strength at weld seam) (-30 ° C) (b.cm) 20 30 <10 <10 20 Sheathing impact according to Izod's test (20 ° C) (kg.cm/cm2) 49.5 25.0 27 , 0 56.5

Thermal deformation temperature (1820 kN / m2, 25 without curing) (° C) 105.0 119.5 104.0 102.5

Processability (Koka-type flow tester, 230 ° C, 60 kg / cm2) (ml / min) 0.47 0.10 0.55 0.50 4 Bending module, x 10 30 (kg / cm2) 2.23 2, 2 2.35 2.0

Claims (4)

A thermoplastic polymer blend having improved welding strength based on a polycarbonate resin, a graft copolymer and a copolymer, characterized in that it comprises a) a polycarbonate resin and b-1) a graft copolymer prepared by graft polymerization of at least two monomers selected from aromatic vinyl compounds, vinyl cyanides and alkyl esters of unsaturated carboxylic acids on conjugated diene gums or ethylene-propylene gums, the weight ratio of rubber to monomers being between 5:95 and 70:30, b-2) a copolymer of at least two monomers selected from aromatic vinyl compounds, vinyl cyanides and alkyl esters of unsaturated carboxylic acids, wherein b-1) represents 10-100% of b-1) + b-2) and b-2) represents 90-0% of b-1) + b-2), and c ) an epoxy group-containing olefin copolymer. Polymer blend according to claim 1, 15, characterized in that the weight ratio of the polycarbonate resin a) to the total amount of the graft copolymer b-1) and the copolymer b-2) is 10: 90-90: 10. Polymer blend according to claim 1, characterized in that the amount of epoxy group-containing olefin copolymer c) is 0.1-40 parts by weight per minute. 100 parts by weight of the mixture. Polymer blend according to claim 1, characterized in that the amount of epoxy group-containing olefin copolymer c) is 0.5-10 parts by weight and up to 100 parts by weight of the mixture.