Resin composition for molding

Abstract

The present invention provides a resin composition for molding that can provide a molded body having excellent heat resistance and excellent mechanical properties as well as high surface smoothness. The present invention also provides a molded body and a pipe each including the resin composition for molding. Provided is a resin composition for molding containing: a chlorinated polyvinyl chloride; a thermal stabilizer; and an impact resistance modifier, the chlorinated polyvinyl chloride having a chlorine content of 63 to 72% by mass, the thermal stabilizer containing a calcium-containing compound and a zinc-containing compound, the resin composition containing the thermal stabilizer in an amount of 0.4 to 10.0 parts by mass and the impact resistance modifier in an amount of 1.0 to 10.0 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; a thermal stabilizer; and an impact resistance modifier, the chlorinated polyvinyl chloride having a chlorine content of 63 to 72% by mass, the thermal stabilizer comprising a calcium-containing compound and a zinc-containing compound, the impact resistance modifier being in a particle form and having an average particle size of 0.1 to 200 μm, and the resin composition comprising the thermal stabilizer in an amount of 0.4 to 10.0 parts by mass and the impact resistance modifier in an amount of 1.0 to 10.0 parts by mass relative to 100 parts by mass of the chlorinated polyvinyl chloride.

2. The resin composition for molding according to claim 1, wherein the chlorinated polyvinyl chloride has structural units (a) to (c) represented by the following formulae (a) to (c):
—CC1.sub.2-  (a),
—CHC1-  (b),
—CH.sub.2-  (c), wherein the proportion of the structural unit (a) is 17.5 mol % or less, the proportion of the structural unit (b) is 46.0 mol % or more, and the proportion of the structural unit (c) is 37.0 mol % or less, relative to the total number of moles of the structural units (a), (b), and (c).

3. The resin composition for molding according to claim 1, comprising the chlorinated polyvinyl chloride in an amount of 70% by mass or more.

4. The resin composition for molding according to claim 1, wherein the impact resistance modifier comprises a methyl methacrylate-butadiene-styrene copolymer and/or an acrylonitrile-butadiene-styrene copolymer.

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

6. The resin composition for molding according to claim 1, having a heat deformation temperature (HDT) of 110° C. or higher as measured in accordance with ASTM D648.

7. The resin composition for molding according to claim 1, having a cell class of at least 2-4-4-4-8 as defined in ASTM D1784.

8. The resin composition for molding according to claim 1, having a notched Izod impact strength at a notched portion of 266.9 J/m or higher.

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

10. A pipe molded from the resin composition for molding according to claim 1.

11. The pipe according to claim 10, which is used for hot water and cool water.

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)

(9) Polyethylene lubricant (available from Mitsui Chemicals, Inc., Hiwax 220MP)

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

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

(12) 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.

(13) (Preparation of Chlorinated Polyvinyl Chloride Composition)

(14) To 100 parts by mass of the obtained chlorinated polyvinyl chloride (degree of polymerization: 1,000) were added 1.5 parts by mass of calcium stearate and 1.0 part by mass zinc stearate as a thermal stabilizer and 6.0 parts by mass of MBS-1 resin as an impact resistance modifier. They were then mixed. The following MBS-1 resin was used.

(15) MBS-1 (methyl methacrylate-butadiene-styrene copolymer) resin having a methyl methacrylate component content of 28% by mass, a diene component content of 52% by mass, and an average particle size of 0.1 μm

(16) Furthermore, 0.3 parts by mass of pentaerythrityl-tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] (hindered phenolic antioxidant, available from BASF, Irganox 1010) as an antioxidant was added and mixed.

(17) Then, 1.0 part by mass of a polyethylene lubricant (available from Mitsui Chemicals, Inc., Hiwax 220MP), 0.5 parts by mass of an ester lubricant (available from Emery Oleochemicals Japan Ltd., LOXIOL G-15), and 3.0 parts by mass of titanium dioxide (available from Ishihara Sangyo Kaisha, Ltd., TIPAQUE CR-90) were added. They were uniformly mixed in a super mixer to give a chlorinated polyvinyl chloride composition.

(18) (Preparation of Extrudate)

(19) 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 209.0° C., a back pressure of 280.0 kg/cm.sup.2, and an extrusion amount of 25.0 kg/hr.

Examples 2 to 21 and Comparative Examples 2 to 7

(20) A chlorinated polyvinyl chloride composition and an extrudate were produced as in Example 1 except that the type and amount of the chlorinated polyvinyl chloride, thermal stabilizer, impact resistance modifier, and lubricant used were as shown in Table 1.

(21) In Examples 7 and 8, ABS resin (acrylic component content: 34% by mass, diene component content: 53% by mass) was used instead of the MBS-1 resin.

(22) In Examples 20 and 21, MBS-2 resin (methyl methacrylate component content: 25% by mass, diene component content: 60% by mass, average particle size: 0.1 μm) and MBS-3 resin (methyl methacrylate component content: 25% by mass, diene component content: 40% by mass, average particle size: 0.3 μm) were used instead of the MBS-1 resin.

(23) In Example 15, an acrylic improver (methyl methacrylate-acrylic rubber copolymer, available from Mitsubishi Chemical Corporation, METABLEN W-450) was used.

(24) In Example 16, a silicon improver (silicone acrylic rubber, available from Mitsubishi Chemical Corporation, METABLEN S-2001) was used.

Comparative Example 1

(25) A chlorinated polyvinyl chloride composition and an extrudate were produced as in Example 1 except that 2.5 parts by mass of a tin thermal stabilizer (butyl tin mercaptide, available from Galata Chemicals, Mark 292) was used as the thermal stabilizer instead of 1.5 parts by mass of calcium stearate and 1.0 part by mass of zinc stearate.

(26) <Evaluation>

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

(28) [Evaluation of Chlorinated Polyvinyl Chloride Composition]

(29) <Mechanical properties (Izod impact strength, tensile strength, tensile modulus of elasticity, and thermal deformation temperature)>

(30) 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 100° C. for 24 hours.

(31) <Cell Class>

(32) The cell class as defined in ASTM D1784 was determined.

(33) [Evaluation of Molded Body]

(34) <Surface Roughness>

(35) 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.

(36) <Filtered Waviness>

(37) The filtered waviness center line average (filtered center line waviness, WcA) and the filtered waviness unevenness (Wct) of the outer surface were 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.

(38) TABLE-US-00001 TABLE 1 Examples 1 2 3 4 5 6 7 Composition Chlorinated polyvinyl 100 100 100 — — 100 100 (parts by chloride (chlorine mass) content: 67.3% by mass) Chlorinated polyvinyl — — — 100 — — — chloride (chlorine content: 64.0% by mass) Chlorinated polyvinyl — — — — 100 — — chloride (chlorine content: 70.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 72.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 62.0% by mass) Chlorinated polyvinyl 127 127 127 110 166 127 127 chloride gelling time (seconds) Chlorinated polyvinyl 88.3% 89.8% 84.2% 88.3% 88.3% 91.5% 91.5% chloride content in the entire composition Thermal Calcium laurate — — — — — — — stabilizer Calcium stearate 1.5 0.4 4.5 1.5 1.5 1.5 1.5 Calcium montanate — — — — — — — Zinc stearate 1.0 0.2 3.5 1.0 1.0 1.0 1.0 Zinc laurate — — — — — — — Tin thermal stabilizer — — — — — — — Total thermal 2.5 0.6 8.0 2.5 2.5 2.5 2.5 stabilizer content Proportion of Ca In the entire composition 0.09% 0.02% 0.25% 0.09% 0.09% 0.09% 0.09% Impact MBS-1 6.0 6.0 6.0 6.0 6.0 2.0 — resistance MBS-2 — — — — — — — modifier MBS-3 — — — — — — — ABS — — — — — — 2.0 Acrylic Improver — — — — — — — Sillcone Improver — — — — — — — Mass ratio 2.4 10.0 0.8 2.4 2.4 0.8 0.8 (impact resistance improver/thermal stabilizer) Antioxidant 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Polyethylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 lubricant Ester lubricant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Titanium oxide 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Evaluation Physical Izod impact strength (J/m) 529 510 520 490 505 250 140 (chlorinated properties Tensile strength (MPa) 51 52 48.9 45 57 53 52 polyvinyl Tensile modulus of 2,580 2,740 2,490 2,490 2,840 2,630 2,650 chloride elasticity (MPa) composition) Thermal deformation 115 116 114 111 118 116 116 temperature (° C.) Cell class 24448 24448 24448 24348 24548 23448 23448 Evaluation Inner Filtered center 1.09 1.22 1.27 0.94 0.89 1.54 1.85 (molded profile line waviness (WcA) product) Filtered waviness 6.5 4.2 5.6 4.0 4.5 6.2 8.0 unevenness (Wct) Surface roughness (Rmax) 0.61 0.77 0.69 0.51 1.88 0.87 0.94 Examples 8 9 10 11 12 13 14 Composition Chlorinated polyvinyl 100 100 100 100 100 — 100 (parts by chloride (chlorine mass) content: 67.3% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 64.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 70.0% by mass) Chlorinated polyvinyl — — — — — 100 — chloride (chlorine content: 72.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 62.0% by mass) Chlorinated polyvinyl 127 127 127 127 127 175 127 chloride gelling time (seconds) Chlorinated polyvinyl 86.7% 86.7% 88.3% 88.3% 88.3% 88.3% 86.8% chloride content in the entire composition Thermal Calcium laurate — — 1.5 — — — — stabilizer Calcium stearate 1.5 1.5 — — 1.5 1.5 4.0 Calcium montanate — — — 1.5 — — — Zinc stearate 1.0 1.0 1.0 1.0 — — — Zinc laurate — — — — 1.0 1.0 0.5 Tin thermal stabilizer — — — — — — — Total thermal 2.5 2.5 2.5 2.5 2.5 2.5 4.5 stabilizer content Proportion of Ca In the entire composition 0.09% 0.09% 0.12% 0.06% 0.09% 0.09% 0.23% Impact MBS-1 — 8.0 6.0 6.0 6.0 6.0 6.0 resistance MBS-2 — — — — — — — modifier MBS-3 — — — — — — — ABS 8.0 — — — — — — Acrylic Improver — — — — — — — Sillcone Improver — — — — — — — Mass ratio 3.2 3.2 2.4 2.4 2.4 2.4 1.3 (impact resistance improver/thermal stabilizer) Antioxidant 0.3 0.3 0.3 0.3 0.3 0.3 02 Polyethylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 lubricant Ester lubricant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Titanium oxide 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Evaluation Physical Izod impact strength (J/m) 300 730 482 543 520 390 300 (chlorinated properties Tensile strength (MPa) 48.5 48.8 51 51 51 53 51 polyvinyl Tensile modulus of 2,500 2,500 2,550 2,530 2,520 2,630 2,520 chloride elasticity (MPa) composition) Thermal deformation 114 113 115 115 115 116 115 temperature (° C.) Cell class 24448 25448 24448 25448 24448 24448 24448 Evaluation Inner Filtered center 1.96 1.00 123 1.55 1.43 1.98 1.17 (molded profile line waviness (WcA) product) Filtered waviness 9.5 4.2 5.3 7.1 6.0 9.8 4.7 unevenness (Wct) Surface roughness (Rmax) 1.02 0.99 1.59 1.64 1.48 1.94 0.65 Examples 15 16 17 18 19 20 21 Composition Chlorinated polyvinyl 100 100 100 100 100 100 100 (parts by chloride (chlorine mass) content: 67.3% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 64.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 70.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 72.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 62.0% by mass) Chlorinated polyvinyl 127 127 127 127 127 127 127 chloride gelling time (seconds) Chlorinated polyvinyl 88.3% 88.3% 86.7% 87.0% 86.5% 93.2% 93.2% chloride content in the entire composition Thermal Calcium laurate — — — — — — — stabilizer Calcium stearate 1.5 1.5 1.0 0.7 12 1.5 1.5 Calcium montanate — — — — — — — Zinc stearate 1.0 1.0 0.5 0.4 0.6 1.0 1.0 Zinc laurate — — — — — — — Tin thermal stabilizer — — — — — — — Total thermal 2.5 2.5 1.5 1.1 1.8 2.5 2.5 stabilizer content Proportion of Ca In the entire composition 0.09% 0.09% 0.06% 0.04% 0.07% 0.09% 0.09% Impact MBS-1 — — 9.0 9.0 9.0 — — resistance MBS-2 — — — — — 6.0 — modifier MBS-3 — — — — — — 6.0 ABS — — — — — — — Acrylic Improver 6.0 — — — — — — Sillcone Improver — 6.0 — — — — — Mass ratio 2.4 2.4 6.0 8.2 5.0 2.4 2.4 (impact resistance improver/thermal stabilizer) Antioxidant 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Polyethylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 lubricant Ester lubricant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Titanium oxide 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Evaluation Physical Izod impact strength (J/m) 410 300 690 720 760 529 529 (chlorinated properties Tensile strength (MPa) 51 50 49 49 49 51 51 polyvinyl Tensile modulus of 2,580 2,580 2,500 2,490 2,510 2,580 2,580 chloride elasticity (MPa) composition) Thermal deformation 114 113 111 110 111 115 115 temperature (° C.) Cell class 24448 24448 24448 24448 24448 24448 24448 Evaluation Inner Filtered center 1.5 1.3 128 1.13 1.42 1.09 1.09 (molded profile line waviness (WcA) product) Filtered waviness 6.3 5.8 5.8 4.8 5.9 6.5 6.5 unevenness (Wct) Surface roughness (Rmax) 0.7 0.83 1.02 0.96 1.15 0.61 0.61 Comparative Examples 1 2 3 4 5 6 7 Composition Chlorinated polyvinyl 100 100 100 — 100 100 100 (parts by chloride (chlorine mass) content: 67.3% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 64.0% by mass) Chlorinated polyvinyl — — — — — — — chloride (chlorine content: 70.0% by mass) Chlorinated polyvinyl — chloride (chlorine content: 72.0% by mass) Chlorinated polyvinyl — — — 100 — — — chloride (chlorine content: 62.0% by mass) Chlorinated polyvinyl 127 127 127 103 127 127 127 chloride gelling time (seconds) Chlorinated polyvinyl 88.3% 90.1% 82.1% 88.3% 92.8% 83.8% 84.9% chloride content in the entire composition Thermal Calcium laurate — — — — — — — stabilizer Calcium stearate — 0.1 6.0 1.5 1.5 1.5 0.7 Calcium montanate — — — — — — — Zinc stearate — 0.1 5.0 1.0 1.0 1.0 0.3 Zinc laurate — — — — — — — Tin thermal stabilizer 2.5 — — — — — — Total thermal 2.5 0.2 11.0 2.5 2.5 2.5 1.0 stabilizer content Proportion of Ca In the entire composition — 0.01% 0.33% 0.09% 0.09% 0.08% 0.04% Impact MBS-1 6.0 6.0 6.0 6.0 0.5 1.2 12.0 resistance MBS-2 — — — — — — — modifier MBS-3 — — — — — — — ABS — — — — — — — Acrylic Improver — — — — — — — Sillcone Improver — — — — — — — Mass ratio 2.4 30.0 0.5 2.4 0.2 4.8 12.0 (impact resistance improver/thermal stabilizer) Antioxidant 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Polyethylene 1.0 1.0 1.0 1.0 1.0 1.0 1.0 lubricant Ester lubricant 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Titanium oxide 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Evaluation Physical Izod impact strength (J/m) 530 581 420 530 140 840 850 (chlorinated properties Tensile strength (MPa) 49 53 48 42 54 45 45 polyvinyl Tensile modulus of 2,490 2,670 2,550 2,280 2,680 2,330 2,300 chloride elasticity (MPa) composition) Thermal deformation 108 117 112 108 116 113 113 temperature (° C.) Cell class 24447 25448 24448 24337 23448 25338 25338 Evaluation Inner Filtered center 0.35 5.81 3.49 0.56 1.27 2.48 2.32 (molded profile line waviness (WcA) product) Filtered waviness 3.2 13.3 12.9 3.7 5.6 13.5 11.4 unevenness (Wct) Surface roughness (Rmax) 0.49 2.8 1.95 0.44 3.5 1.81 2.55

INDUSTRIAL APPLICABILITY

(39) The present invention can provide a resin composition for molding that can provide a molded body having excellent heat resistance and excellent mechanical properties as well as high surface smoothness. The present invention can also provide a molded body and a pipe each including the resin composition for molding.