CHLORINATED VINYL CHLORIDE RESIN

Abstract

The present invention provides a chlorinated polyvinyl chloride that enables excellent continuous productivity in molding and that enables a molded article to have both processability and unevenness-preventing properties. Provided is a chlorinated polyvinyl chloride having an endothermic peak start temperature (L) and an endothermic peak end temperature (H) that satisfy the following expression (1) in endothermic peak measurement using a differential scanning calorimeter (DSC): 41° C.≤H−L≤98° C. (1).

Claims

1. A chlorinated polyvinyl chloride having an endothermic peak start temperature (L) and an endothermic peak end temperature (H) that satisfy the following expression (1) in endothermic peak measurement using a differential scanning calorimeter (DSC): 41° C.≤H−L≤98° C. (1).

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

3. A molded body molded from the resin composition for molding according to claim 2.

Description

DESCRIPTION OF EMBODIMENTS

[0109] 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

[0110] A glass-lined reaction vessel having an inner capacity of 300 L was charged with 130 kg of ion-exchanged water and 50 kg of a polyvinyl chloride having an average degree of polymerization of 1,000. They were stirred to disperse the polyvinyl chloride 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, while stirring was performed with a stirring blade such that the vortex formed at the liquid-gas interface by stirring had a vortex volume of 2.5 L, 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. At this time, the height of the stirring blade was adjusted such that the ratio of the distance from liquid surface to the stirring blade to the height of the liquid surface (the distance from the liquid surface to the stirring blade/the height of the liquid surface) was 0.155 (m/m). The ratio of the stirring blade diameter to the reaction vessel diameter (the stirring blade diameter/the stirring blade diameter) was 0.54 (m/m). 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 10.6% by mass, the ultraviolet irradiation using the high-pressure mercury lamp and the chlorine gas supply were terminated, whereby chlorination was completed.

[0111] Subsequently, unreacted chlorine was removed by nitrogen gas aeration, and the obtained chlorinated polyvinyl chloride slurry was neutralized with sodium hydroxide, washed with water, dehydrated, and then dried.

[0112] Thus, a powdery, photo-chlorinated polyvinyl chloride (amount of added chlorine: 10.6% by mass) was obtained.

Examples 2 to 4 and Comparative Example 1

[0113] Chlorinated polyvinyl chlorides were obtained as in Example 1 except that the reaction temperature, the vortex volume in stirring, the distance from the liquid surface to the stirring blade/the height of liquid surface, the average chlorine consumption rate were changed as shown in Tables 1 and 2.

Example 5

[0114] A glass-lined reaction vessel having an inner capacity of 300 L was charged with 130 kg of ion-exchanged water and 50 kg of a polyvinyl chloride having an average degree of polymerization of 1,000. They were stirred to disperse the polyvinyl chloride 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 100° C. Subsequently, the inside of the reaction vessel was depressurized to remove oxygen (oxygen content 100 ppm). Thereafter, while stirring was performed with a stirring blade such that the vortex formed at the liquid-gas interface by stirring had a vortex volume of 8.3 L, chlorine (oxygen content 50 ppm) was introduced at a partial pressure of chlorine of 0.40 MPa, thereby starting thermal chlorination. At this time, the height of the stirring blade was adjusted such that the ratio of the distance from liquid surface to the stirring blade to the height of the liquid surface (the distance from the liquid surface to the stirring blade/the height of the liquid surface) was 0.390 (m/m). The ratio of the stirring blade diameter to the reaction vessel diameter (the stirring blade diameter/the reaction vessel diameter) was 0.54 (m/m). Then, the chlorination temperature was kept at 100° C. and the partial pressure of chlorine was kept at 0.40 MPa. After the amount of added chlorine reached 4.2% 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, and the average chlorine consumption rate was adjusted to 0.02 kg/PVC−kg.Math.5 min. Thereafter, when the amount of added chlorine reached 10.3% by mass, the supply of hydrogen peroxide solution and chlorine gas was terminated, whereby chlorination was completed.

[0115] Subsequently, unreacted chlorine was removed by nitrogen gas aeration, and the obtained chlorinated polyvinyl chloride slurry was neutralized with sodium hydroxide, washed with water, dehydrated, and then dried. Thus, a powdery, thermally chlorinated polyvinyl chloride (amount of added chlorine: 10.3% by mass) was obtained.

Examples 6 to 10 and Comparative Examples 2 to 9

[0116] Chlorinated polyvinyl chlorides were obtained as in Example 5 except that the reaction temperature, the vortex volume in stirring, the distance from the liquid surface to the stirring blade/the height of the liquid surface, the average chlorine consumption rate, and the amount of 200 ppm hydrogen peroxide added were changed as shown in Tables 1 and 2.

Examples 11 to 13

[0117] Chlorinated polyvinyl chlorides were obtained as in Example 5 except that the average degree of polymerization of the polyvinyl chloride, the vortex volume in stirring, the distance from the liquid surface to the stirring blade/the height of the liquid surface, and the average chlorine consumption rate were changed as shown in Table 1.

(Evaluation)

[0118] The chlorinated polyvinyl chlorides obtained in the examples and the comparative examples were evaluated as follows. Tables 1 and 2 show the results.

(1) Amount of Added Chlorine

[0119] The amount of added chlorine was measured for each of the obtained chlorinated polyvinyl chlorides in conformity with JIS K 7229.

(2) Molecular Structure Analysis

[0120] The molecular structure of each of the obtained chlorinated polyvinyl chlorides 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).

[0121] The NMR measurement conditions were as follows.

[0122] Apparatus: FT-NMRJEOLJNM-AL-300

[0123] Measured nuclei: 13C (proton complete decoupling)

[0124] Pulse width: 90°

[0125] PD: 2.4 sec

[0126] Solvent: o-dichlorobenzene:deuterated benzene (C5D5)=3:1

[0127] Sample concentration: about 20%

[0128] Temperature: 110° C.

[0129] Reference material: central signal for benzene set to 128 ppm

[0130] Number of scans: 20,000

(3) Differential Scanning Calorimetry (DSC)

[0131] Each of the obtained chlorinated polyvinyl chlorides was heated using a differential scanning calorimetry (DSC) device (produced by TA Instruments Waters Corporation, DSC Q20) from 40° C. to 200° C. at a heating rate of 5° C./min and then cooled from 200° C. to 40° C. at a cooling rate of 5° C./min.

[0132] The same procedure was performed again, and from the DSC curve obtained in the second heating, data at 0.1-minute intervals from the start of the second heating was extracted so as to graph the difference in heat flow at 0.1-minute intervals. The maximum and minimum differences in heat flow at 0.1-minute intervals were determined, and then the average difference in heat flow in the range of 50° C. to 60° C. was calculated. The average difference in heat flow in the range of 50° C. to 60° C. was subtracted from the difference in heat flow at 0.1 minute-intervals in the temperature range of 60° C. or higher. The first temperature at which the value calculated by the subtraction exceeded 0.00001 ten consecutive times was determined, whereby the endothermic peak start temperature (L) was determined. Further, the average difference in heat flow in the range of 50° C. to 60° C. was subtracted from the difference in heat flow at 0.1-minute intervals in the temperature range above the temperature at which the maximum difference in heat flow at 0.1-minute intervals occurred. The first temperature at which the value calculated by the subtraction falls below −0.00001 was determined, whereby the end temperature of the endothermic peak (H) was determined. H−L was calculated based on the endothermic peak start temperature (L) and the endothermic peak end temperature (H).

(4) Developed Interfacial Area Ratio (Sdr)

(Production of Chlorinated Polyvinyl Chloride Composition)

[0133] An amount of 5.5 parts by mass of an impact resistance modifier was added to 100 parts by mass of each of the obtained chlorinated polyvinyl chlorides. Then, 1.5 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).

[0134] 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 uniformly mixed in a super mixer, whereby a chlorinated polyvinyl chloride composition was obtained.

(Production of Extrusion-Molded Body)

[0135] The obtained chlorinated polyvinyl chloride composition was fed into a twin-screw counter-rotating conical extruder with a diameter of 50 mm (produced by Osada Seisakusho, SLM-50) to prepare a sheet-shaped molded body with a thickness of 2 mm and a width of 80 mm at a resin temperature of 205° C., a back pressure of 130 kg/cm.sup.2, and an extrusion amount of 40 kg/hr.

(Sdr Measurement)

[0136] The Sdr value of a surface of the obtained molded body was measured using a 3D measurement system (produced by Keyence Corporation, VR-3100). Each Sdr value shown in Table 1 is the average of five measurement regions.

[0137] Sdr is a ratio representing the degree of increase in the surface area of the measured region compared to the area of the measured region. A completely level surface has an Sdr of 0. A molded body having a low Sdr has excellent smoothness. Using such a molded body as, for example, a pipe-shaped molded body for plumbing or the like can reduce noise when water is running.

(5) Scorch Marks (Discoloration) of Molded Body

[0138] The surface state of the obtained molded body was visually examined and evaluated in accordance with the following criteria.

∘ (Good): No scorch mark (discoloration) was observed.
x (Poor): Scorch mark(s) (discoloration) was/were observed.

(6) Surface Shape (Unevenness)

[0139] The surface shape of the molded body was examined visually and by touch, and evaluated in accordance with the following criteria.

∘ (Good): Neither the visual examination nor the touch examination found surface irregularities.
Δ (Fair): The visual examination found no surface irregularities but the touch examination found surface irregularities.
x (Poor) The visual examination found surface irregularities.

(7) Continuous Productivity

[0140] The obtained chlorinated polyvinyl chloride composition was fed into a twin-screw counter-rotating conical extruder with a diameter of 50 mm (produced by Osada Seisakusho, “SLM-50”) to prepare sheet-shaped molded bodies with a thickness of 2 mm and a width of 80 mm at a resin temperature of 205° C., a back pressure of 130 kg/cm.sup.2, and an extrusion amount of 40 kg/hr. The time from the start of the molding to the occurrence of a scorch mark (discoloration) in the obtained molded body was measured, and the continuous productivity was evaluated.

[0141] A longer time before the occurrence of a scorch mark (discoloration) in the molded body indicates that the chlorinated polyvinyl chloride is less likely to contaminate the die surface and enables excellent continuous productivity when products are continuously produced by repeating similar operations for a long time.

TABLE-US-00001 TABLE 1 Examples 1 2 3 4 5 Production Raw Average degree of 1000 1000 1000 1000 1000 method material polymerization PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 Chlorination Reaction temperature ° C. 70 100 100 100 100 conditions Reacton pressure Mpa 0.04 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume in L 2.5 7.5 25.2 27 8.3 stirring Vortex volume/ L/kg 0.014 0.042 0.140 0.150 0.046 (PVC + water) (Distance from liquid m/m 0.155 0.365 0.684 0.690 0.390 surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc − 0.02 0.006 0.012 0.005 0.02 consumption rate kg .Math. 5 min 200 ppm hydrogen ppm/hr — — — — 15 peroxide Peak wavelength nm 365 365 365 365 — Chlorinated Amount of added chlorine mass % 10.6 10.5 10.5 10.5 10.3 polyvinyl Structure Structural unit (a) mol % 35.8 35.7 35.3 34.6 36.9 chloride —CH.sub.2—CHCl— Structural unit (b) mol % 24.6 24 24 32 24 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 39.6 40.3 40.7 33.4 39.1 —CHCl—CHCl— DSC Start temperature (L) ° C. 104 105 76 74 86 End temperature (H) ° C. 150 153 169 171 156 H − L ° C. 46 48 93 97 70 Maximum heat W/g 0.00036 0.00037 0.00023 0.00020 0.00030 flow difference Minimum heat W/g 0.00001 0.00007 0.00003 0.00004 0.00000 flow difference Amount of J/g 3.046 2.746 2.585 2.466 2.821 absorbed heat Molded Sdr 0.0001 0.0014 0.0029 0.0029 0.0013 body Scorch mail (discoloration) ∘ ∘ ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ ∘ ∘ Continuous productivity (hr) 10.5 10 6 4 11.5 Examples 6 7 8 9 10 Production Raw Average degree of 1000 1000 1000 1000 1000 method material polymerization PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 Chlorination Reaction temperature ° C. 100 100 100 100 100 conditions Reacton pressure Mpa 0.40 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume L 19.6 7.5 7.6 7.5 1.8 in stirring Vortex volume/ L/kg 0.109 0.042 0.042 0.042 0.010 (PVC + water) (Distance from liquid m/m 0.480 0.374 0.374 0.374 0.104 surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc − 0.02 0.011 0.006 0.005 0.006 consumption rate kg .Math. 5 min 200 ppm hydrogen ppm/hr 15 15 15 15 15 peroxide Peak wavelength nm — — — — — Chlorinated Amount of added chlorine mass % 10.6 5.3 12.5 15.5 10.5 polyvinyl Structure Structural unit (a) mol % 35.5 67.5 24 5.4 35.3 chloride —CH.sub.2—CHCl— Structural unit (b) mol % 24.7 9 28 39.8 24.8 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 39.8 23.5 48 54.8 39.9 —CHCl—CHCl— DSC Start temperature (L) ° C. 76 86 103 123 105 End temperature (H) ° C. 165 130 165 187 154 H − L ° C. 89 44 62 65 49 Maximum heat W/g 0.00021 0.00023 0.00035 0.00037 0.00038 flow difference Minimum heat W/g 0.00010 0.00006 0.00007 0.00013 0.00007 flow difference Amount of J/g 2.599 3.010 2.582 2.246 2.935 absorbed heat Molded Sdr 0.0013 0.0018 0.0022 0.0032 0.0027 body Scorch mail (discoloration) ∘ ∘ ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ Δ ∘ Continuous productivity (hr) 7.5 5.1 6.5 4.1 5 Examples 11 12 13 Production Raw material Average degree of polymerization 450 1500 2100 method PVC Charge amount kg 50 50 50 Water Ion-exchanged water kg 130 130 130 Chlorination Reaction temperature ° C. 100 100 100 conditions Reacton pressure Mpa 0.40 0.40 0.40 PVC + water kg 180 180 180 Vortex volume in stirring L 7.5 7.5 7.5 Vortex volume/(PVC + water) L/kg 0.042 0.042 0.042 (Distance from liquid m/m 0.365 0.365 0.365 surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc − 0.009 0.011 0.012 consumption rate kg .Math. 5 min 200 ppm hydrogen peroxide ppm/hr 15 15 15 Peak wavelength nm — — — Chlorinated Amount of added chlorine mass % 10.5 10.5 9.7 polyvinyl Structure Structural unit (a) mol % 35.2 30.2 40.2 chloride —CH.sub.2—CHCl— Structural unit (b) mol % 24 23.5 22.2 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 40.8 46.3 37.6 —CHCl—CHCl— DSC Start temperature (L) ° C. 104 92 83 End temperature (H) ° C. 153 163 173 H − L ° C. 49 71 90 Maximum heat flow difference W/g 0.00030 0.00022 0.00020 Minimum heat flow difference W/g 0.00009 0.00008 0.00010 Amount of absorbed heat J/g 3.022 3.005 3.032 Molded Sdr 0.0020 0.0022 0.0023 body Scorch mail (discoloration) ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ Continuous productivity (hr) 4.4 4.5 4

TABLE-US-00002 TABLE 2 Comparative Examples 1 2 3 4 5 Production Raw Average degree of 1000 1000 1000 1000 350 method material polymerization PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged kg 130 130 130 130 130 water Chlorination Reaction ° C. 80 140 100 100 100 conditions temperature Reaction pressure Mpa 0.04 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume L 0.9 32 1.1 27 28.8 in stirring Vortex volume/ L/kg 0.005 0.178 0.006 0.150 0.160 (PVC + water) (Distance from m/m 0.032 0.980 0.040 0.750 0.905 liquid surface to stirring blade)/Height of liquid surface Average chlorine kg/pvc − 0.010 0.030 0.006 0.150 0.018 consumption rate kg .Math. 5 min 200 ppm ppm/hr — 50 15 15 15 hydrogen peroxide Peak wavelength nm 365 — — — — Chlorinated Amount of added chlorine mass % 10.6 10.5 10.5 2.5 10.5 polyvinyl Structure Structural unit (a) mol % 34.1 34.2 34.6 84.4 36 chloride —CH.sub.2—CHCl— Structural unit (b) mol % 31.1 41 40.7 5 32 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 34.8 24.8 24.7 10.6 32 —CHCl—CHCl— DSC Start temperature ° C. 109 74 105 75 72 (L) End temperature ° C. 146 173 144 104 172 (H) H − L ° C. 37 99 39 30 100 Maximum heat W/g 0.00039 0.00020 0.00039 0.00020 0.00045 flow difference Minimum heat W/g 0.00007 0.00002 0.00007 0.00006 0.00011 flow difference Amount of J/g 3.052 2.462 3.462 3.982 3.210 absorbed heat Molded Sdr 0.0063 0.0121 0.0082 0.0048 0.0051 body Scorch mark (discoloration) x x x x x Surface shape (unevenness) x x x x x Continuous productivity (hr) 2 1.5 2.5 3 2.2 Comparative Examples 6 7 8 9 Production Raw Average degree of 1000 1000 1000 1000 method material polymerization PVC Charge amount kg 50 50 50 50 Water Ion-exchanged kg 130 130 130 130 water Chlorination Reaction ° C. 100 100 100 100 conditions temperature Reaction pressure Mpa 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 Vortex volume L 1.9 1.4 25.2 26.5 in stirring Vortex volume/ L/kg 0.011 0.008 0.140 0.147 (PVC + water) (Distance from m/m 0.040 0.052 0.800 0.690 liquid surface to stirring blade)/Height of liquid surface Average chlorine kg/pvc − 0.004 0.004 0.016 0.016 consumption rate kg .Math. 5 min 200 ppm ppm/hr 15 15 15 15 hydrogen peroxide Peak wavelength nm — — — — Chlorinated Amount of added chlorine mass % 10.5 10.6 10.3 10.5 polyvinyl Structure Structural unit (a) mol % 35.2 35.2 35.2 35.3 chloride —CH.sub.2—CHCl— Structural unit (b) mol % 40.2 41 29 28 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 24.6 23.8 35.8 36.7 —CHCl—CHCl— DSC Start temperature ° C. 104 104 75 75 (L) End temperature ° C. 144 145 174 174 (H) H − L ° C. 41 42 99 99 Maximum heat W/g 0.00038 0.00037 0.00020 0.00020 flow difference Minimum heat W/g 0.00007 0.00007 0.00006 0.00006 flow difference Amount of J/g 3.122 3.154 3.284 3.280 absorbed heat Molded Sdr 0.0045 0.0042 0.0039 0.004 body Scorch mark (discoloration) x x x x Surface shape (unevenness) Δ Δ Δ Δ Continuous productivity (hr) 3.5 3.4 3.5 3.5

INDUSTRIAL APPLICABILITY

[0142] The present invention can provide a chlorinated polyvinyl chloride that enables excellent continuous productivity in molding and that enables a molded article to have both processability and unevenness-preventing properties.