CHLORINATED VINYL CHLORIDE-BASED RESIN

Abstract

The present invention provides a chlorinated polyvinyl chloride resin that enables the production of a molded article that maintains high adhesion strength even when used in a form subjected to high pressure and is less susceptible to defects such as cracks due to insufficient strength, as well as a resin composition for molding and a molded article each including the chlorinated polyvinyl chloride resin. Provided is a chlorinated polyvinyl chloride resin having an average of a ratio (A/B) of a peak intensity A observed in a range of 300 to 340 cm.sup.-1 to a peak intensity B observed in a range of 1,450 to 1,550 cm.sup.-1 of 0.1 or more and 3.5 or less in Raman imaging measurement by Raman spectroscopy.

Claims

1. A chlorinated polyvinyl chloride resin having an average of a ratio (A/B) of a peak intensity A observed in a range of 300 to 340 cm.sup.-1 to a peak intensity B observed in a range of 1,450 to 1,550 cm.sup.-1 of 0.1 or more and 3.5 or less in Raman imaging measurement by Raman spectroscopy.

2. The chlorinated polyvinyl chloride resin according to claim 1, wherein a standard deviation of the ratio (A/B) of the peak intensity A to the peak intensity B is 0.10 to 10.0 in Raman imaging measurement by Raman spectroscopy.

3. The chlorinated polyvinyl chloride resin according to claim 1, which has a sulfur content of 1 mass ppm or more and 1,000 mass ppm or less.

4. A resin composition for molding, comprising the chlorinated polyvinyl chloride resin according to claim 1.

5. A molded article molded from the resin composition for molding according to claim 4.

Description

DESCRIPTION OF EMBODIMENTS

[0123] The present invention is hereinafter described in more detail with reference to examples; however, the present invention should not be limited to these examples.

Example 1

[0124] A glass-lined reaction vessel having an inner capacity of 300 L was charged with 130 kg of deionized water and 50 kg of a polyvinyl chloride resin having an average degree of polymerization of 1,000. They were stirred to disperse the polyvinyl chloride resin in water to prepare an aqueous suspension, and then the inside of the reaction vessel was heated to raise the temperature of the aqueous suspension to 70° C. Subsequently, the inside of the reaction vessel was depressurized to remove oxygen (oxygen content 100 ppm). Thereafter, with stirring, chlorine (oxygen content 50 ppm) was introduced at a partial pressure of chlorine of 0.04 MPa, and the suspension was irradiated with ultraviolet light having a wavelength of 365 nm at an irradiation intensity of 160 W using a high-pressure mercury lamp, thereby starting chlorination reaction.

[0125] Then, the chlorination temperature was kept at 70° C., the partial pressure of chlorine was kept at 0.04 MPa, and the average chlorine consumption rate was adjusted to 0.02 kg/PVC-kg.Math.5 min. When the amount of added chlorine reached 9.5% by mass, the ultraviolet irradiation using the high-pressure mercury lamp and the chlorine gas supply were terminated, whereby chlorination was terminated.

[0126] Subsequently, unreacted chlorine was removed by nitrogen gas aeration, and the obtained chlorinated polyvinyl chloride resin slurry was neutralized with sodium hydroxide, washed with water, and dehydrated in a centrifuge (produced by Tanabe Tekkosho K.K., 0-15 model) for three minutes.

[0127] After dehydration, 0.1 parts by mass (0.05 kg) of 2-ethylhexyl thioglycolate (produced by FUJIFILM Wako Pure Chemical Corporation) as a sulfur compound was added to 100 parts by mass (50 kg) of the chlorinated polyvinyl chloride resin at 200 g/min. This was followed by stationary drying at 90° C. for 12 hours. Thus, a powdery, photo-chlorinated polyvinyl chloride resin (amount of added chlorine: 9.5% by mass) was obtained.

Comparative Example 1

[0128] A glass-lined reaction vessel having an inner capacity of 300 L was charged with 130 kg of deionized water and 50 kg of a polyvinyl chloride resin having an average degree of polymerization of 1,000. They were stirred to disperse the polyvinyl chloride resin in water to prepare an aqueous suspension, and then the inside of the reaction vessel was heated to raise the temperature of the aqueous suspension to 140° C. Subsequently, the inside of the reaction vessel was depressurized to remove oxygen (oxygen content 100 ppm). Thereafter, with stirring, chlorine (oxygen content 50 ppm) was introduced at a partial pressure of chlorine of 0.04 MPa, thereby starting thermal chlorination.

[0129] Then, the chlorination temperature was kept at 140° C. and the partial pressure of chlorine was kept at 0.40 MPa. After the amount of added chlorine reached 4.4% by mass, addition of a 200 ppm hydrogen peroxide solution was started at 15 ppm/Hr in terms of hydrogen peroxide relative to the polyvinyl chloride resin, and the average chlorine consumption rate was adjusted to 0.05 kg/PVC-kg.Math.5 min. When the amount of added chlorine reached 9.5% by mass, the supply of hydrogen peroxide solution and chlorine gas was terminated, whereby chlorination was terminated.

[0130] Subsequently, unreacted chlorine was removed by nitrogen gas aeration, and the obtained chlorinated polyvinyl chloride resin slurry was neutralized with sodium hydroxide, washed with water, and dehydrated in a centrifuge (produced by Tanabe Tekkosho K.K., 0-15 model) for three minutes. This was followed by stationary drying at 90° C. for 12 hours. Thus, a powdery, thermally chlorinated polyvinyl chloride resin (amount of added chlorine: 9.5% by mass) was obtained.

Examples 2 to 15 and Comparative Examples 2 and 3

[0131] A powdery chlorinated polyvinyl chloride resin was obtained as in Example 1 except that chlorination was performed at the reaction temperature, reaction pressure, average chlorine consumption rate (upper value in each cell in the table: the rate after the amount of added chlorine reached five percentage points by mass from the final amount of added chlorine; lower value: the rate after the amount of added chlorine reached three percentage points by mass from the final amount of added chlorine) as shown in Table 1, then a sulfur compound was added in the shown amount, and drying was performed at the shown drying temperature for the shown drying time.

Comparative Example 4

[0132] A powdery chlorinated polyvinyl chloride resin was obtained as in Comparative Example 1 except that chlorination was performed at the average chlorine consumption rate shown in Table 1 and then drying was performed at the shown drying temperature and the shown drying time.

Example 16

[0133] A chlorinated polyvinyl chloride resin (amount of added chlorine 10.7% by mass) was obtained as in Example 3 except that the sulfur compound was added in the amount shown in Table 1 and drying was performed at 100° C. for 45 hours using a vibrating fluidized bed dryer (produced by Chuo Kakohki Co., Ltd., VU-75 model).

Evaluation

[0134] The chlorinated polyvinyl chloride resins obtained in the examples and the comparative examples were evaluated as follows. Table 1 shows the results.

Raman Imaging Measurement

[0135] An amount of 300 parts by mass of THF was added to 10 parts by mass of each of the powdery chlorinated polyvinyl chloride resins obtained in Examples 1 to 16 and Comparative Examples 1 to 4, stirred for 24 hours for dissolution, followed by further stirring in a centrifuge (produced by Kokusan Co., Ltd., H-200NR) at 14,000 rpm for 1 hour to precipitate insoluble components. The insoluble components were filtered out, and to the filtrate was added 1,000 parts by mass of methanol to reprecipitate the resin. While the resin was washed with methanol, suction filtration was performed using an aspirator (produced by AS ONE Corporation, GAS-IN) to separate the resin from the filtrate. The obtained resin was put in a vacuum drier (produced by Tokyo Rikakikai Co., Ltd., VOS-451SD) and dried at 80° C. for 24 hours to prepare a sample. The sample was heated in a gear oven (produced by Toyo Seiki Seisaku-Sho, Ltd., CO-O2) at 150° C. for 10 minutes, and the sample was subjected to Raman spectrum measurement using a Raman microscope (produced by inVia Qontor, Renishaw plc.).

[0136] In the obtained Raman spectra, two peaks around 307 cm.sup.-1 and 357 cm.sup.-1 observed in the range of 245 cm.sup.-1 to 420 cm.sup.-1 were subjected to peak separation using this range as the baseline. The peak height of the peak observed around 300 to 340 cm.sup.-1 with respect to the baseline was determined as the peak intensity A. Two peaks around 1,495 cm.sup.-1 and 1,427 cm.sup.-1 observed in the range of 1,400 to 1,600 cm.sup.-1 were subjected to peak separation using this range as the baseline. The peak height of the peak observed around 1,450 to 1,550 cm.sup.-1 with respect to the baseline was determined as the peak intensity B. The ratio (A/B) of the peak intensity A to the peak intensity B was then calculated, and average of the A/B and the standard deviation were also calculated. For the calculation of the average of the A/B and the standard deviation, the region of an acrylic resin was excluded, and only the region of the chlorinated polyvinyl chloride resin was used.

Measurement of the Amount of Added Chlorine

[0137] The amount of added chlorine was measured for each of the obtained chlorinated polyvinyl chloride resins in conformity with JIS K 7229.

Molecular Structure Analysis

[0138] The molecular structure of each of the obtained chlorinated polyvinyl chloride resins was analyzed in conformity with the NMR measurement method described in R. A. Komoroski, R. G. Parker, J. P. Shocker, Macromolecules, 1985, 18, 1257-1265 so as to determine the amount of the structural units (a), (b), and (c).

[0139] The NMR measurement conditions were as follows. [0140] Apparatus: FT-NMRJEOLJNM-AL-300 [0141] Measured nuclei: 13C (proton complete decoupling) [0142] Pulse width: 90° [0143] PD: 2.4 sec [0144] Solvent: o-dichlorobenzene:deuterated benzene (C5D5) = 3:1 [0145] Sample concentration: about 20% [0146] Temperature: 110° C. [0147] Reference material: central signal for benzene set to 128 ppm [0148] Number of scans: 20,000

Measurement of Sulfur Content of Chlorinated Polyvinyl Chloride Resin

[0149] An amount of 300 parts by mass of THF was added to 10 parts by mass of each of the obtained chlorinated polyvinyl chloride resins, stirred for 24 hours for dissolution, followed by further stirring in a centrifuge (produced by Kokusan Co., Ltd., H-200NR) at 14,000 rpm for 1 hour to precipitate insoluble components. The insoluble components were filtered out, and to the filtrate was added 1,000 parts by mass of methanol to reprecipitate the resin. While the resin was washed with methanol, suction filtration was performed using an aspirator (produced by AS ONE Corporation, GAS-IN) to separate the resin from the filtrate. In this manner, a sulfur-bound resin was obtained. The resin was put in a vacuum drier (produced by Tokyo Rikakikai Co., Ltd., VOS-451SD) and dried at 80° C. for 24 hours. Combustion IC was performed to detect CS bonds. The obtained sample is weighed in a ceramic boat, and then burned in an automatic sample combustion device. The generated gas is captured in 10 mL of an absorber liquid. This absorber liquid is adjusted to 15 mL with ultrapure water, and subjected to IC quantitative analysis. After a linear approximation of a SO.sub.4.sup.2- anion calibration curve by measurement of a reference substance, the sample is measured to quantify the sulfur content (% by weight) of the chlorinated polyvinyl chloride resin.

[0150] The measurement conditions for the automatic combustion device are as follows. [0151] Device: AQF-2100H, produced by Mitsubishi Chemical Analytech [0152] Inlet temperature: 1,000° C. [0153] Outlet temperature: 1,100° C. [0154] Gas flow rate O.sub.2: 400 mL/min [0155] Gas flow rate Ar: 200 mL/min [0156] Ar water supply unit: 100 mL/min [0157] The conditions for IC are as follows. [0158] Device: ICS-5000, produced by Thermo Fisher Scientific [0159] Separation column: Dionex IonPac AS18-4 .Math.m (2 mm × 150 mm) [0160] Guard column: Dionex IonPac AG18-4 .Math.m (2 mm × 30 mm) [0161] Suppressor system: Dionex AERS-500 (external mode) [0162] Detector: conductivity detector [0163] Eluent: aqueous KOH solution (eluent generator EGC500) [0164] Eluent flow rate: 0.25 mL/min [0165] Sample injection volume: 100 .Math.L

Adhesion Evaluation

Preparation of Pipe

[0166] An amount of 4.0 parts by mass of an impact resistance modifier was added to 100 parts by mass of each of the obtained chlorinated polyvinyl chloride resins. Then, 0.5 parts by mass of a thermal stabilizer was added and mixed. The impact resistance modifier used was Kane Ace B-564 (produced by Kaneka Corporation, methyl methacrylate-butadiene-styrene copolymer). The thermal stabilizer used was TVS#1380 (produced by Nitto Kasei Co., Ltd., organotin stabilizer).

[0167] Further, 1.5 parts by mass of a polyethylene lubricant (produced by Mitsui Chemicals, Inc., Hiwax 220MP) and 0.2 parts by mass of a fatty acid ester lubricant (produced by Emery Oleochemicals Japan Ltd., LOXIOL G-32) were added. They were then uniformly mixed in a super mixer to prepare a chlorinated polyvinyl chloride resin composition.

[0168] The obtained chlorinated polyvinyl chloride resin composition was supplied to a conical counter-rotating twin screw extruder (produced by Osada Seisakusho, SLM-50) having a diameter of 50 mm and formed into pipes at a resin temperature of 200° C., each pipe having an outer diameter of 26.7 mm and a wall thickness of 2.4 mm.

Preparation of Joint

[0169] An amount of 5.0 parts by mass of an impact resistance modifier was added to 100 parts by mass of a chlorinated polyvinyl chloride resin (produced by Sekisui Chemical Co., Ltd., HA-24KL). Further, 3.0 parts by mass of a thermal stabilizer was added and mixed. The impact resistance modifier used was Kane Ace M-511 (produced by Kaneka Corporation, methyl methacrylate-butadiene-styrene copolymer). The thermal stabilizer used was TVS#1380 (produced by Nitto Kasei Co., Ltd., organotin stabilizer).

[0170] Further, 2.0 parts by mass of a polyethylene lubricant (produced by Mitsui Chemicals, Inc., Hiwax 220MP) and 0.3 parts by mass of a fatty acid ester lubricant (produced by Emery Oleochemicals Japan Ltd., LOXIOL G-32) were added. They were then uniformly mixed in a super mixer to prepare a chlorinated polyvinyl chloride resin composition.

[0171] The obtained chlorinated polyvinyl chloride resin composition was supplied to a conical counter-rotating twin screw extruder (produced by Osada Seisakusho, OSC-30) having a diameter of 30 mm and formed into pellets at a resin temperature of 190° C. The obtained pellets were supplied to an injection molding machine (produced by JSW, J350ADS) and formed into a socket having an outer diameter of 34.7 mm and an inner diameter of 26.9 mm.

Preparation of Assembled Sample

[0172] Two of the obtained pipes were cut to a length of 20 cm and bonded to the two ends of the obtained joint using an adhesive (produced by IPS, WELD-ON 724). The workpiece was then left to stand at 23° C. for 14 days, and left to stand in an oven (produced by Toyo Seiki Seisaku-Sho, Ltd., CO—O2) at 82° C. for 2 days, whereby an assembled sample was obtained.

Adhesion Evaluation

[0173] The inside of the obtained assembled sample was filled with water. The test was started by pressurizing the pipes to a hoop stress of 15.93 MPa using a hydrostatic pressure resistance tester (produced by IPT, 1662-0021) in an atmosphere adjusted to 65° C. with an oven. The time until a disconnection occurred between the pipe and joint to which the adhesive was applied was measured.

[0174] The adhesion was evaluated as “o” (Good) when no disconnection was observed after 1,000 hours from the start of the test, and evaluated as “x” (Poor) when a disconnection occurred by 1,000 hours. For the cases where a disconnection occurred by 1,000 hours, the time at which the disconnection occurred is shown in the table.

Molded Article Strength Evaluation

[0175] The presence or absence of cracks or fractures in the pipes and joint were determined after “(5) Adhesion evaluation”, and the molded article strength was evaluated in accordance with the following criteria. [0176] ◯ (Good): No crack or fracture was observed after 1,000 hours. [0177] Δ (Fair): Slight whitening was observed after 1,000 hours. No water leakage due to cracks or fractures was observed. [0178] x (Poor): Cracks or fractures were observed by 1,000 hours.

TABLE-US-00001 Example Comparative Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 2 3 4 Production method Raw material PVC Average degree of polymerization 1000 1000 1000 1000 1000 700 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 Charge kg 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 130 Chlorination conditions Reaction temperature °C 70 70 70 70 70 70 70 70 70 70 70 50 80 70 70 70 140 85 50 140 Reaction pressure Mpa 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.02 1.50 0.04 0.04 0.04 0.40 0.04 0.04 0.40 PVC + water kg 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 180 Average chlorine consumption rate kg/pvc-kg.Math. 5 min 0.02 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.010/ 0.005 0.015/ 0.010 0.013/ 0.009 0.011/ 0.006 0.012/ 0.007 0.012/ 0.007 0.012/ 0.007 0.05 0.020/ 0.015 0.008/ 0.004 0.050/ 0.030 UV wavelength nm 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 - 365 365 - 200 ppm hydrogen peroxide ppm/hr - - - - - - - - - - - - - - - - 15 - - 15 Amount of 2-ethylhexyl thioglycolate added parts by mass 0.1 0.1 9.2 0.004 4.8 1.5 1.5 0.04 0.002 0.04 0.003 0.04 0.005 - - 8.8 0 11.2 0.0001 0 Amount of isooctyl thioglycolate added parts by mass - - - - - - - - - - - - - 1.5 - - - - - - Amount of butanediol bisthioglycolate added parts by mass - - - - - - - - - - - - - - 1.5 - - - - - Drying conditions Drying temperature °C 90 80 100 80 80 80 80 65 100 80 80 80 80 80 80 100 90 100 55 80 Drying time hr 12 12 40 12 12 12 12 40 7 12 12 12 12 12 12 45 12 5 50 12 Chlorinated polyvinyl chloride resin Amount of added chlorine mass% 9.5 127 10.7 10.7 10.7 10.6 5.7 10.7 10.7 10.7 10.7 10.7 10.7 10.7 10.7 10.7 95 107 10.7 107 Structure Structural unit (b)—CH.sub.2—CCl.sub.2— mol% 24.2 29.4 22.5 23.1 24.7 24.3 92 25.1 23.8 24.7 22.2 21.9 22.5 24.1 23.6 19.4 20.2 30.6 24.9 25.3 Raman imaging spectroscopy Peak intensity A/B Average 2.81 0.2 3.3 1.8 2.4 1.2 3.4 2.3 0.8 3.1 0.2 0.3 1.3 1.0 0.8 3.4 7.05 0.02 4.6 6.2 Standard deviation 0.58 3.9 5.2 0.3 0.4 0.3 0.6 0.2 5.3 0.3 6.9 1.1 7.1 0.4 0.6 4.1 0.08 11.2 0.4 0.2 (Average of A/B) + (Standard deviation of A/B).sup.½ 3.57 2.2 5.6 2.3 3.0 1.7 42 2.7 3.1 3.6 2.8 1.3 4.0 1.6 1.6 5.4 7.3 3.4 5.2 6.6 (Amount of added chlorine)/(Average of A/B) 3.4 63.6 3.2 5.9 4.5 8.8 1.7 4.7 13.4 3.5 53.5 35.7 8.2 10.7 13.4 3.1 1.3 53.5 23 1.7 (Average of A/B)/((Amount of added chlorine) × (Structural unit (b)) 0.0122 0.0005 0.0137 0.0073 0.0091 0.0047 0.0648 0.0086 0.0031 0.0117 0.0008 0.0013 0 0054 0.0039 0.0032 0.0164 0.0367 0.0001 0.02 0.02 Sulfur content of resin (mass ppm) 14 21 182 13 47 35 18 11 6 12 7 11 8 30 24 842 0 105 0 0 Evaluation Adhesion Disconnection hr 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 40 101 80 250 Rating o o o o o o o o o o o o o o o o x x x x Molded article strength Rating o o o o o o o Δ Δ o Δ o Δ o o o o x x x

INDUSTRIAL APPLICABILITY

[0179] The present invention can provide a chlorinated polyvinyl chloride resin that enables the production of a molded article that maintains high adhesion strength even when used in a form subjected to high pressure and is less susceptible to defects such as cracks due to insufficient strength, as well as a resin composition for molding and a molded article each including the chlorinated polyvinyl chloride resin.