Resin composition for molding

Abstract

The present invention provides a resin composition for molding that can provide a molded body having excellent thermal stability, high impact resistance, and high surface smoothness. The present invention also provides a molded body including the resin composition for molding. Provided is a resin composition for molding including: a chlorinated polyvinyl chloride; an acrylic processing aid; and an impact resistance modifier, the acrylic processing aid containing an acrylic resin having a weight average molecular weight of 500,000 to 5,000,000, the resin composition containing the acrylic processing aid in an amount of 0.2 to 10 parts by mass and the impact resistance modifier in an amount of 0.5 to 8.0 parts by mass relative to 100 parts by mass of the chlorinated polyvinyl chloride.

Claims

1. A resin composition for molding comprising: a chlorinated polyvinyl chloride; an acrylic processing aid; and an impact resistance modifier, the acrylic processing aid comprising an acrylic resin having a weight average molecular weight of 1,100,000 to 2,400,000, a diene component content of a polymer constituting the impact resistance modifier is 35 to 65% by mass, the resin composition comprising the acrylic processing aid in an amount of 0.2 to 10 parts by mass and the impact resistance modifier in an amount of 5.5 to 8.0 parts by mass relative to 100 parts by mass of the chlorinated polyvinyl chloride, and the chlorinated polyvinyl chloride having structural units (a) to (c) represented by the following formulae (a) to (c):
CCl.sub.2(a),
CHCl(b),
CH.sub.2(c), wherein a proportion of the structural unit (a) is 17.5 mol % or less, a proportion of the structural unit (b) is 46.0 mol % or more, and a proportion of the structural unit (c) is 37.0 mol % or less, relative to a total number of moles of the structural units (a), (b), and (c).

2. The resin composition for molding according to claim 1, wherein the chlorinated polyvinyl chloride has a chlorine content of 63 to 72% by mass.

3. The resin composition for molding according to claim 1, wherein the acrylic resin is a polymer of methyl (meth)acrylate.

4. The resin composition for molding according to claim 1, wherein the impact resistance modifier is a methyl methacrylate-butadiene-styrene copolymer.

5. The resin composition for molding according to claim 1, wherein the ratio of the impact resistance modifier to the acrylic processing aid (impact resistance modifier/acrylic processing aid) is 7.0 or less.

6. The resin composition for molding according to claim 1, further comprising a thermal stabilizer.

7. The resin composition for molding according to claim 1, which is free from -diketone.

8. The resin composition for molding according to claim 6, comprising the thermal stabilizer in an amount of 0.4 to 10 parts by mass relative to 100 parts by mass of the chlorinated polyvinyl chloride.

9. A molded body molded from the resin composition for molding according to claim 1.

10. The resin composition for molding according to claim 1, wherein the impact resistance modifier differs from the acrylic processing aid.

11. The resin composition for molding according to claim 1, further comprising an antioxidant, wherein the antioxidant has a loss in quantity on heating at 200 C. of less than 5% by mass.

12. The resin composition for molding according to claim 1, wherein the chlorinated polyvinyl chloride has a gelling time of 100 to 200 seconds.

13. The resin composition for molding according to claim 1, further comprising two or more lubricants.

Description

DESCRIPTION OF EMBODIMENTS

(1) The present invention will be hereinafter described in more detail with reference to examples; however, the invention should not be construed as being limited to these examples.

Example 1

(2) (Preparation of Chlorinated Polyvinyl Chloride)

(3) A glass-lined reaction vessel with an internal volume of 300 L was charged with 200 kg of ion-exchange water and 56 kg of a polyvinyl chloride with a degree of polymerization of 1,000. The mixture was stirred, and water was further added to the reaction vessel to disperse the mixture in the water. The pressure was subsequently reduced to remove oxygen from the reaction vessel, and the temperature was simultaneously elevated to 90 C.

(4) Chlorine was then supplied into the reaction vessel so that the chlorine partial pressure would be 0.4 MPa, and the chlorination reaction was performed while adding 0.2% by mass hydrogen peroxide at a rate of 1 part by mass per hour (320 ppm/hour). The reaction was continued until the chlorine content of the chlorinated polyvinyl chloride reached 61% by mass. When the chlorine content of the chlorinated polyvinyl chloride reached 61% by mass (five percentage points by mass lower than the final chlorine content), the amount of 0.2% by mass hydrogen peroxide added was reduced to 0.1 parts by mass per hour (200 ppm/hour), and the average chlorine consumption rate was adjusted to 0.012 kg/PVC-kg.Math.5 min, and then the chlorination was allowed to proceed. Further, when the chlorine content reached 63% by mass (three percentage points by mass lower than the final chlorine content), the amount of 0.2% by mass hydrogen peroxide added was reduced to 150 ppm/hour, and the average chlorine consumption rate was adjusted to 0.008 kg/PVC-kg.Math.5 min, and then the chlorination was allowed to proceed. In this way, a chlorinated polyvinyl chloride having a chlorine content of 67.3% by mass was obtained. The chlorine content of the chlorinated polyvinyl chloride was measured in accordance with JIS K 7229.

(5) The gelling time of the chlorinated polyvinyl chloride was measured by the following method.

(6) (Gelling Time Measurement)

(7) A compound sample was prepared by adding 1.2 parts by mass of a thermal stabilizer, 1.0 part by mass of a polyethylene lubricant, 0.5 parts by mass of a polyethylene oxide lubricant, and 5.5 parts by mass of an impact resistance modifier to 100 parts by mass of the chlorinated polyvinyl chloride. The thermal stabilizer, polyethylene lubricant, polyethylene oxide lubricant, impact resistance modifier used were as follows.

(8) Thermal stabilizer (available from Nitto Kasei Co., Ltd., TVS #1380) Polyethylene lubricant (available from Mitsui Chemicals, Inc., Hiwax 220MP)

(9) Polyethylene oxide lubricant (available from Honeywell International Inc., A-C 316A)

(10) Impact resistance modifier (available from Kaneka Corporation, Kane Ace M-511)

(11) Subsequently, 59 g of the compound sample was put in Labo PlastoMill (available from Toyo Seiki Seisaku-Sho, Ltd., 4C150) at a temperature of 180 C. and pre-heated for 80 seconds. The rotor was then rotated at a frequency of 30 rpm. The time at which the motor torque reached its maximum was determined as the gelling time.

(12) (Preparation of Chlorinated Polyvinyl Chloride Composition)

(13) To 100 parts by mass of the obtained chlorinated polyvinyl chloride (degree of polymerization: 1,000) were added 1.5 parts by mass of polymethyl methacrylate (available from Mitsubishi Rayon Co., Ltd., weight average molecular weight: 800,000, glass transition temperature: 75 C., melting temperature: 136 C.) as an acrylic processing aid and 5.5 parts by mass of an impact resistance modifier. Furthermore, 1.5 parts by mass of a thermal stabilizer and 0.5 parts by mass of pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (hindered phenolic antioxidant, Irganox 1010, available from BASF, loss in quantity on heating at 200 C.: 1.0% by mass) as an antioxidant were added, followed by mixing. The impact resistance modifier used was MBS-1 (methyl methacrylate-butadiene-styrene copolymer, methyl methacrylate component content: 25% by mass, diene component content: 55% by mass, average particle size: 0.3 m) resin (available from LG Chem Ltd., glass transition temperature of butadiene alone: 93 C.). The thermal stabilizer (organotin stabilizer) used was dimethyltin bis(2-ethylhexyl thioglycolate).

(14) Then, 2.0 parts by mass of a polyethylene lubricant (available from Mitsui Chemicals, Inc., Hiwax 220MP), 0.3 parts by mass of a fatty acid ester lubricant (available from Emery Oleochemicals Japan Ltd., LOXIOL G-32), and 6.0 parts by mass of titanium dioxide (available from Ishihara Sangyo Kaisha, Ltd., TIPAQUE CR-90) were added. This was followed by uniform mixing in a super mixer to give a chlorinated polyvinyl chloride composition.

(15) (Preparation of Extrudate)

(16) The obtained chlorinated polyvinyl chloride composition was fed into a twin-screw counter-rotating conical extruder with a diameter of 50 mm (Osada Seisakusho; SLM-50) to prepare a pipe-shaped extrudate with an internal diameter of 20 mm and a thickness of 3 mm at a resin temperature of 209.8 C., a back pressure of 291.0 kg/cm.sup.2, and an extrusion amount of 24.3 kg/hr.

Examples 2 to 14 and Comparative Examples 1 to 6

(17) A chlorinated polyvinyl chloride composition and an extrudate were prepared as in Example 1 except that polymethyl methacrylate having a weight average molecular weight (Mw) and a melting temperature as shown in Table 1 and an impact resistance modifier were used in the amounts shown in Table 1. In Example 11, the impact resistance modifier used was ABS (available from Galata Chemicals, Blendex 338, acrylonitrile-butadiene-styrene copolymer) resin.

(18) In Examples 12 and 13, calcium stearate and zinc stearate were used instead of dimethyltin bis(2-ethylhexyl thioglycolate).

(19) In Example 14, MBS-2 (methyl methacrylate-butadiene-styrene copolymer, methyl methacrylate component content: 25% by mass, diene component content: 40% by mass, average particle size: 0.3 m) was used instead of MBS-1.

(20) The conditions for extrusion molding were changed as shown in Table 1.

Example 15

(21) A chlorinated polyvinyl chloride composition and an extrudate were prepared as in Example 1 except that a chlorinated polyvinyl chloride having a gelling time shown in Table 1 was used.

(22) <Evaluation>

(23) The chlorinated polyvinyl chloride compositions and extrudates obtained in the examples and the comparative examples were evaluated as follows. Table 1 shows the results.

(24) [Evaluation of Chlorinated Polyvinyl Chloride Composition]

(25) <Mechanical Properties (Izod Impact Strength, Tensile Strength, Tensile Modulus of Elasticity, and Thermal Deformation Temperature)>

(26) The obtained chlorinated polyvinyl chloride composition was fed to two 8-inch rolls, and kneaded at 205 C. for 3 minutes to prepare 1.0-mm-thick sheets. The obtained sheets were layered, preheated with a press at 205 C. for 3 minutes, and then pressurized for 4 minutes to obtain a 3-mm-thick press plate. The obtained press plate was cut into specimens by machining. With these specimens, the Izod impact strength was measured in accordance with ASTM D256, and the tensile strength and tensile modulus of elasticity were measured in accordance with ASTM D638. The thermal deformation temperature was measured under a load of 186 N/cm.sup.2 in accordance with ASTM D648. The thermal deformation temperature was measured after annealing the obtained press plate in a gear oven at 90 C. for 24 hours.

(27) <Vicat Softening Temperature>

(28) The Vicat softening temperature was measured by a method in accordance with JIS K 7206:2016 (Plastics-Thermoplastic materials-Determination of Vicat softening temperature, B50 method).

(29) [Evaluation of Molded Body]

(30) <Appearance Observation>

(31) The surface state of the pipe-shaped extrudate was visually observed to evaluate the presence or absence of scorching (discoloration).

(32) <Surface Roughness>

(33) The surface roughness (Rmax) was measured using a surface roughness measuring instrument (available from Tokyo Seimitsu Co., Ltd., SURFCOM 480A) by a method in accordance with JIS B 0601. The measurement was performed at an evaluation length of 0.3 mm, a measurement speed of 0.3 mm/sec, and a cut-off value of 0.08 mm.

(34) <Filtered Waviness>

(35) The filtered waviness center line average (filtered center line waviness, WcA) of the outer surface was measured using a surface roughness measuring instrument (available from Tokyo Seimitsu Co., Ltd., SURFCOM 480A) by a method in accordance with JIS B 0601. The measurement was performed at an evaluation length of 30 mm, a measurement speed of 3 mm/sec, and a cut-off value of 0.25 to 8 mm.

(36) TABLE-US-00001 TABLE 1 Examples 1 2 3 4 5 6 Composition Chlorinated polyvinyl chloride Amount 100 100 100 100 100 100 (parts by mass) Acrylic processing aid Gelling time (seonds) 127 127 127 127 127 127 (PMMA) Mw: 800,000 (melting 1.5 temperature: 136 C.) Mw: 1,100,000 (melting 1.5 temperature: 130 C.) Mw: 1,400,000 (melting 1.5 temperature: 118 C.) Mw: 1,450,000 (melting 1.5 temperature: 114 C.) Mw: 2,400,000 (melting 1.5 temperature: 122 C.) Mw: 3,100,000 (melting 1.5 temperature: 119 C.) Mw: 250,000 (melting temperature: 133 C.) Mw: 6,000,000 (melting temperature: 103 C.) Impact resistance modifier MBS-1 5.5 5.5 5.5 5.5 5.5 5.5 MBS-2 ABS Mass ratio (impact resistance 3.7 3.7 3.7 3.7 3.7 3.7 improver/acrylic processing aid) Organotin stabilizer 1.5 1.5 1.5 1.5 1.5 1.5 Calcium stearate Zinc stearate Hindered phenolic antioxidant 0.5 0.5 0.5 0.5 0.5 0.5 Polyethylene lubricant 2.0 2.0 2.0 2.0 2.0 2.0 Fatty acid ester lubricant 0.3 0.3 0.3 0.3 0.3 0.3 Titanium dioxide 6.0 6.0 6.0 6.0 6.0 6.0 Mass ratio (impact resistance 4.69% 4.69% 4.69% 4.69% 4.69% 4.69% improver/entire composition) Mass ratio (acrylic processing 1.28% 1.28% 1.28% 1.28% 1.28% 1.28% aid/entire composition) Extrusion Temperature ( C.) 209.8 210.0 212.0 211.0 212.0 213.0 molding Back pressure (kg/cm.sup.2) 291.0 293.5 300.0 291.0 312.0 314.0 conditions Extruding amount (kg/hr) 24.3 25.1 22.7 22.3 23.3 22.9 Evaluation Mechanical properties IZOD test (J/m) 104.7 111.6 151.1 152.3 131.4 146.2 (chlorinated Tensile strength (MPa) 52.59 53.13 52.3 53.0 52.7 53.1 polyvinyl Tensile modulus of 2625 2612 2708 2720 2781 2770 chloride elasticity (MPa) composition) Thermal deformation 112.9 112.7 113.7 113.7 113.7 113.7 temperature ( C.) Vicat softening 115.3 115.5 115.7 115.3 114.9 115.6 temperature ( C.) Evaluation Apparance Scorching None None None None None None (molded body) Surface roughness Rmax (m) 0.73 0.7 0.9 0.98 0.54 1.06 Filtered center line waviness WcA (m) 1.21 1.09 0.72 1.03 0.73 0.65 Examples 7 8 9 10 11 Composition Chlorinated polyvinyl chloride Amount 100 100 100 100 100 (parts by mass) Acrylic processing aid Gelling time (seonds) 127 127 127 127 127 (PMMA) Mw: 800,000 (melting 0.5 8 1.5 1.5 15 temperature: 136 C.) Mw: 1,100,000 (melting temperature: 130 C.) Mw: 1,400,000 (melting temperature: 118 C.) Mw: 1,450,000 (melting temperature: 114 C.) Mw: 2,400,000 (melting temperature: 122 C.) Mw: 3,100,000 (melting temperature: 119 C.) Mw: 250,000 (melting temperature: 133 C.) Mw: 6,000,000 (melting temperature: 103 C.) Impact resistance modifier MBS-1 5.5 5.5 3 7 MBS-2 ABS 5.5 Mass ratio (impact resistance 11.0 0.7 2.0 4.7 3.7 improver/acrylic processing aid) Organotin stabilizer 1.5 1.5 1.5 1.5 1.5 Calcium stearate Zinc stearate Hindered phenolic antioxidant 0.5 0.5 0.5 0.5 0.5 Polyethylene lubricant 2.0 2.0 2.0 2.0 2.0 Fatty acid ester lubricant 0.3 0.3 0.3 0.3 0.3 Titanium dioxide 6.0 6.0 6.0 6.0 6.0 Mass ratio (impact resistance 4.73% 4.44% 2.61% 5.89% 4.69% improver/entire composition) Mass ratio (acrylic processing 0.43% 6.46% 1.31% 1.26% 1.28% aid/entire composition) Extrusion Temperature ( C.) 208.7 212.5 207.0 215.0 210.1 molding Back pressure (kg/cm.sup.2) 281.0 310.0 265.0 320.0 285.0 conditions Extruding amount (kg/hr) 25.5 21.5 25.1 19.8 23.2 Evaluation Mechanical properties IZOD test (J/m) 133.3 111.1 62 254 99.6 (chlorinated Tensile strength (MPa) 52.4 52.4 56.0 49.0 51.8 polyvinyl Tensile modulus of 2671 2632 2694 2560 2619 chloride elasticity (MPa) composition) Thermal deformation 113.5 113.3 113.5 112.5 112.7 temperature ( C.) Vicat softening 115.9 115.2 115.2 115.3 115.1 temperature ( C.) Evaluation Apparance Scorching None None None None None (molded body) Surface roughness Rmax (m) 1.33 0.5 0.76 1.25 0.76 Filtered center line waviness WcA (m) 1.87 0.99 1.26 1.30 1.19 Examples Comparative Examples 12 13 14 15 1 Composition Chlorinated polyvinyl chloride Amount 100 100 100 100 100 (parts by mass) Acrylic processing aid Gelling time (seonds) 127 127 127 160 127 (PMMA) Mw: 800,000 (melting 15 1.5 1.5 temperature: 136 C.) Mw: 1,100,000 (melting temperature: 130 C.) Mw: 1,400,000 (melting temperature: 118 C.) Mw: 1,450,000 (melting temperature: 114 C.) Mw: 2,400,000 (melting temperature: 122 C.) Mw: 3,100,000 (melting temperature: 119 C.) Mw: 250,000 (melting 1.5 temperature: 133 C.) Mw: 6,000,000 (melting temperature: 103 C.) Impact resistance modifier MBS-1 5.5 5.5 5.5 5.5 MBS-2 5.5 ABS Mass ratio (impact resistance 3.7 3.7 3.7 3.7 3.7 improver/acrylic processing aid) Organotin stabilizer 1.5 1.5 1.5 Calcium stearate 1.5 1.5 Zinc stearate 1.0 1.0 Hindered phenolic antioxidant 0.5 0.5 0.5 0.5 0.5 Polyethylene lubricant 2.0 2.0 2.0 2.0 2.0 Fatty acid ester lubricant 0.3 0.3 0.3 0.3 0.3 Titanium dioxide 6.0 6.0 6.0 6.0 6.0 Mass ratio (impact resistance 4.65% 4.65% 4.69% 4.69% 4.69% improver/entire composition) Mass ratio (acrylic processing 1.27% 1.27% 1.28% 1.28% 1.28% aid/entire composition) Extrusion Temperature ( C.) 209.5 210.3 209.0 209.0 209.0 molding Back pressure (kg/cm.sup.2) 283.3 290.6 291.0 293.0 282.9 conditions Extruding amount (kg/hr) 25.3 24.7 24.5 23.6 24.0 Evaluation Mechanical properties IZOD test (J/m) 124.2 118.7 104 104 94.3 (chlorinated Tensile strength (MPa) 52.2 52.9 52 52.5 52.7 polyvinyl Tensile modulus of 2598 2633 2627 2660 2591 chloride elasticity (MPa) composition) Thermal deformation 113.4 112.5 112 113 113.7 temperature ( C.) Vicat softening 115.6 115 115.3 115.8 115.1 temperature ( C.) Evaluation Apparance Scorching None None None None None (molded body) Surface roughness Rmax (m) 0.75 0.76 0.8 1.92 3.3 Filtered center line waviness WcA(m) 1.19 1.25 1.50 2.40 8.1 Comparative Examples 2 3 4 5 6 Composition Chlorinated polyvinyl chloride Amount 100 100 100 100 100 (parts by mass) Acrylic processing aid Gelling time (seonds) 127 127 127 127 127 (PMMA) Mw: 800,000 (melting 0.1 12 1.5 15 temperature: 136 C.) Mw: 1,100,000 (melting temperature: 130 C.) Mw: 1,400,000 (melting temperature: 118 C.) Mw: 1,450,000 (melting temperature: 114 C.) Mw: 2,400,000 (melting temperature: 122 C.) Mw: 3,100,000 (melting temperature: 119 C.) Mw: 250,000 (melting temperature: 133 C.) Mw: 6,000,000 (melting 1.5 temperature: 103 C.) Impact resistance modifier MBS-1 5.5 55 5.5 0.3 10 MBS-2 ABS Mass ratio (impact resistance 3.7 55.0 0.5 0.2 6.7 improver/acrylic processing aid) Organotin stabilizer 1.5 1.5 1.5 1.5 1.5 Calcium stearate Zinc stearate Hindered phenolic antioxidant 0.5 05 0.5 0.5 0.5 Polyethylene lubricant 2.0 2.0 2.0 2.0 2.0 Fatty acid ester lubricant 0.3 0.3 0.3 0.3 0.3 Titanium dioxide 6.0 6.0 6.0 6.0 6.0 Mass ratio (impact resistance 4.69% 4.75% 4.30% 0.27% 8.21% improver/entire composition) Mass ratio (acrylic processing 1.28% 0.09% 9.39% 1.34% 1.23% aid/entire composition) Extrusion Temperature ( C.) 218.0 208.4 220.0 205.9 221.0 molding Back pressure (kg/cm.sup.2) 380.0 269.0 388.0 247.0 374.0 conditions Extruding amount (kg/hr) 21.0 25.8 19.5 25.4 15.3 Evaluation Mechanical properties IZOD test (J/m) 152.6 133.3 120 30 630 (chlorinated Tensile strength (MPa) 53.6 524 522 56.9 46.0 polyvinyl Tensile modulus of 2801 2671 2685 2681 2504 chloride elasticity (MPa) composition) Thermal deformation 113.5 113.5 112.8 113.1 113 temperature ( C.) Vicat softening 114.9 115.9 115.4 115 115.7 temperature ( C.) Evaluation Apparance Scorching Occured None Occured None Occured (molded body) Surface roughness Rmax (m) 0.6 2.8 0.2 1.38 2.8 Filtered center line waviness WcA (m) 2 3.40 0.40 227 4.90

INDUSTRIAL APPLICABILITY

(37) The present invention can provide a resin composition for molding that can provide a molded body having excellent thermal stability, high impact resistance, and high surface smoothness. The present invention can also provide a molded body including the resin composition for molding.