CHLORINATED VINYL-CHLORIDE-BASED RESIN

Abstract

The present invention provides a chlorinated polyvinyl chloride resin 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 resin having, in Raman measurement by Raman spectroscopy, an average of a ratio (A/B) of a peak intensity A observed in a range of 660 to 700 cm.sup.−1 to a peak intensity B observed in a range of 600 to 650 cm.sup.−1 of 0.50 to 2.00, and a standard deviation of the A/B of 0.090 or less.

Claims

1. A chlorinated polyvinyl chloride resin having, in Raman measurement by Raman spectroscopy, an average of a ratio (A/B) of a peak intensity A observed in a range of 660 to 700 cm.sup.−1 to a peak intensity B observed in a range of 600 to 650 cm .sup.1 of 0.50 to 2.00, and a standard deviation of the A/B of 0.090 or less.

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

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

Description

DESCRIPTION OF EMBODIMENTS

[0102] 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

[0103] A glass-lined reaction vessel having an inner capacity of 300 L was charged with 130 kg of ion-exchanged water, 50 kg of a polyvinyl chloride having an average degree of polymerization of 1,000, and stabilized chlorine dioxide. 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. The stabilized chlorine oxide was added in such a proportion that the amount of chlorine dioxide was 200 ppm relative to the mass of the chlorine introduced in chlorination. 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 7.5 L, chlorine 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 (Distance from liquid surface to stirring blade/Height of liquid surface) was 0.374 (m/m). The ratio of the stirring blade diameter to the reaction vessel diameter (Stirring blade diameter/Reaction vessel diameter) was 0.54 (m/m).

[0104] 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 0.01 kg/PVC-kg.Math.5 min. Thereafter, when the amount of added chlorine reached 10.4% by mass, the supply of hydrogen peroxide solution and chlorine gas was terminated, whereby chlorination was terminated.

[0105] 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, dehydrated, and then dried. Thus, a powdery, thermally chlorinated polyvinyl chloride resin (amount of added chlorine: 10.4% by mass) was obtained.

EXAMPLES 2 to 13 AND COMPARATIVE EXAMPLES 1 to 11

[0106] Chlorinated polyvinyl chloride resins were obtained as in Example 1 except that the average degree of polymerization of the polyvinyl chloride, the ClO.sub.2/Cl.sub.2 concentration, 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.

(Evaluation)

[0107] The chlorinated polyvinyl chloride resins obtained in the examples and the comparative examples were evaluated as follows. Table 1 shows the results.

(1) Measurement of the Amount of Added Chlorine

[0108] The amount of added chlorine was measured for each of the obtained chlorinated polyvinyl chloride resins in conformity with JIS K 7229.

(2) Molecular Structure Analysis

[0109] 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).

[0110] The NMR measurement conditions were as follows. [0111] Apparatus: FT-NMRJEOLJNM-AL-300 [0112] Measured nuclei: 13C (proton complete decoupling) [0113] Pulse width: 90° [0114] PD: 2.4 sec [0115] Solvent: o-dichlorobenzene:deuterated benzene (C5D5)=3:1 [0116] Sample concentration: about 20% [0117] Temperature: 110° C. [0118] Reference material: central signal for benzene set to 128 ppm [0119] Number of scans: 20,000

(3) Particle Raman Spectroscopy

[0120] Raman spectra of the obtained chlorinated polyvinyl chloride resins were measured using a micro-Raman spectrometer (produced by Thermo Fisher Scientific K.K., Almega XR). Here, the Raman spectra were measured for randomly collected 50 particles of each of the obtained powdery chlorinated polyvinyl chloride resin using a laser with a wavelength of 532 nm at an exposure time of 1 second and a scan number of 32. Raman spectroscopic analysis of particles themselves allows for obtaining the peak intensities of the particle surfaces. The wavenumbers of the Raman shifts were calibrated with the metal silicon peak at 520.5 cm .sup.−1.

[0121] The obtained Raman spectra were baseline-corrected by linear approximation using a baseline from 515 cm.sup.−1 to a local minimum observed at 750 to 950 cm.sup.−1. Furthermore, the peak intensity B observed in the range of 600 to 650 cm.sup.−1 (mainly 641 cm.sup.−1) and the peak intensity A observed in the range of 660 to 700 cm.sup.−1 (mainly 697 cm.sup.−1) were measured, and the ratio (A/B) of the peak intensity A to the peak intensity B was calculated. The average of the A/B of the 50 particles and the standard deviation of the A/B were calculated.

(4) Developed Interfacial Area Ratio (Sdr)

(Production of Chlorinated Polyvinyl Chloride Resin Composition)

[0122] 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 chloride resins. 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).

[0123] 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 resin composition was obtained.

(Production of Extrusion-Molded Article)

[0124] The obtained chlorinated polyvinyl chloride resin 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 article 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)

[0125] The Sdr value of a surface of the obtained molded article 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.

[0126] 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 article having a low Sdr has excellent smoothness. Using such a molded article as, for example, a pipe-shaped molded article for plumbing or the like can reduce noise when water is running.

(5) Residual Water Droplet

[0127] The obtained molded article (thickness 2 mm, width 80 mm, and length 150 mm) was immersed in water for 10 seconds, taken out of the water perpendicularly to the longitudinal direction at a speed of 150 mm/sec using tweezers, and held for 10 seconds. The surface of the molded article was then observed to visually determine the presence or absence of a water droplet having a diameter of 0.5 mm or more. The evaluation was performed in accordance with the following criteria. [0128] ○ (Good): No water droplet having a diameter of 0.5 mm or more was observed. [0129] × (Poor): Water droplet(s) having a diameter of 0.5 mm or more was/were observed.

[0130] The absence of a water droplet on the surface of the molded article indicates that the obtained molded article, for example a pipe-shaped molded article, has few water droplets remaining thereon when water flows therethrough, and thus has excellent antifungal properties.

(6) Scorch Marks (Discoloration) of Molded Article

[0131] The surface state of the obtained molded article was visually examined and evaluated in accordance with the following criteria. [0132] ○ (Good): No scorch mark (discoloration) was observed. [0133] × (Poor): Scorch mark(s) (discoloration) was/were observed.

(7) Surface Shape (Unevenness)

[0134] The surface shape of the molded article was examined visually and by touch, and evaluated in accordance with the following criteria. [0135] ○ (Good): Neither the visual examination nor the touch examination found surface irregularities. [0136] Δ (Fair): The visual examination found no surface irregularities but the touch examination found surface irregularities. [0137] × (Poor) The visual examination found surface irregularities.

(8) Continuous Productivity

[0138] The obtained chlorinated polyvinyl chloride resin 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 articles 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 article was measured, and the continuous productivity was evaluated.

[0139] A longer time before the occurrence of a scorch mark (discoloration) in the molded article indicates that the chlorinated polyvinyl chloride resin 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 material Average degree of polymerization 1000 1000 1000 1000 1000 method PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 Additive ClO.sub.2/Cl.sub.2 ppm 200 4,900 200 200 200 concentration Chlorination Reaction temperature ° C. 100 100 100 100 100 conditions Reaction pressure Mpa 0.40 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume in L 7.5 20.5 7.6 7.5 7.5 stirring Vortex volume/ L/kg 0.042 0.114 0.042 0.042 0.042 (PVC + water) (Distance from m/m 0.374 0.496 0.374 0.374 0.374 liquid surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc-kg .Math. 0.01 0.005 0.01 0.011 0.012 consumption rate 5 min 200 ppm hydrogen ppm/hr 15 15 15 15 15 peroxide Chlorinated Amount of added chlorine mass % 10.4 10.5 3.3 0.2 3.3 polyvinyl Structure Structural unit (a) mol % 36.5 36.1 80.2 98.8 80.6 chloride —CH.sub.2—CHCl— resin Structural unit (b) mol % 24 24.2 7.1 0.1 6 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 39.5 39.7 12.7 1.1 13.4 —CHCl—CHCl— Raman Peak intensity Average 1.249 1.260 0.550 0.731 0.796 spectroscopic A/B Standard 0.038 0.076 0.008 0.011 0.013 analysis deviation (Peak average of A/B) + 1.445 1.536 0.639 0.836 0.910 (Standard deviation).sup.1/2 Molded Sdr 0.0010 0.0028 0.0015 0.0005 0.0012 article Residual water droplet ∘ ∘ ∘ ∘ ∘ Scorch mark (discoloration) ∘ ∘ ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ ∘ ∘ Continuous productivity (hr) 8.2 7.5 4.8 6 7 Examples 6 7 8 9 10 Production Raw material Average degree of polymerization 1000 1000 350 450 1900 method PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 Additive ClO.sub.2/Cl.sub.2 ppm 200 200 200 200 200 concentration Chlorination Reaction temperature ° C. 100 100 100 100 100 conditions Reaction pressure Mpa 0.40 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume in L 7.6 7.5 7.4 7.5 7.5 stirring Vortex volume/ L/kg 0.042 0.042 0.041 0.042 0.042 (PVC + water) (Distance from m/m 0.374 0.374 0.374 0.374 0.374 liquid surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc-kg .Math. 0.007 0.006 0.008 0.009 0.008 consumption rate 5 min 200 ppm hydrogen ppm/hr 15 15 15 15 15 peroxide Chlorinated Amount of added chlorine mass % 13.3 15 10.3 10.5 12 polyvinyl Structure Structural unit (a) mol % 19.3 5.2 36.9 35.8 27.0 chloride —CH.sub.2—CHCl— resin Structural unit (b) mol % 29.1 39.9 33 24 24.2 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 51.6 54.9 30.1 40.2 48.8 —CHCl—CHCl— Raman Peak intensity Average 1.461 1.860 1.193 1.203 1.348 spectroscopic A/B Standard 0.052 0.078 0.023 0.028 0.068 analysis deviation (Peak average of A/B) + 1.689 2.139 1.345 1.370 1.609 (Standard deviation).sup.1/2 Molded Sdr 0.0025 0.0028 0.0019 0.0020 0.0029 article Residual water droplet ∘ ∘ ∘ ∘ ∘ Scorch mark (discoloration) ∘ ∘ ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ ∘ ∘ Continuous productivity (hr) 6.6 5.1 4 4.4 4.5 Examples 11 12 13 Production Raw material Average degree of polymerization 1000 1000 1000 method PVC Charge amount kg 50 50 50 Water Ion-exchanged water kg 130 130 130 Additive ClO.sub.2/Cl.sub.2 ppm 2,450 200 200 concentration Chlorination Reaction temperature ° C. 100 100 100 conditions Reaction pressure Mpa 0.40 0.40 0.40 PVC + water kg 180 180 180 Vortex volume in L 7.5 2 25.2 stirring Vortex volume/ L/kg 0.042 0.011 0.140 (PVC + water) (Distance from m/m 0.374 0.118 0.684 liquid surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc-kg .Math. 0.006 0.005 0.014 consumption rate 5 min 200 ppm hydrogen ppm/hr 15 15 15 peroxide Chlorinated Amount of added chlorine mass % 10.4 10.5 10.6 polyvinyl Structure Structural unit (a) mol % 35.0 35.8 35.3 chloride —CH.sub.2—CHCl— resin Structural unit (b) mol % 38.8 23.2 24 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 26.2 41 40.7 —CHCl—CHCl— Raman Peak intensity Average 1.250 1.268 1.260 spectroscopic A/B Standard 0.085 0.078 0.076 analysis deviation (Peak average of A/B) + 1.542 1.547 1.536 (Standard deviation).sup.1/2 Molded Sdr 0.0029 0.0025 0.0026 article Residual water droplet ∘ ∘ ∘ Scorch mark (discoloration) ∘ ∘ ∘ Surface shape (unevenness) ∘ ∘ ∘ Continuous productivity (hr) 5.6 5.1 7.6

TABLE-US-00002 TABLE 2 Comparative Examples 1 2 3 4 5 6 Production Raw material Average degree of polymerization 1000 1000 1000 2100 1000 1000 method PVC Charge amount kg 50 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 130 Additive ClO.sub.2/Cl.sub.2 ppm 7,350 200 200 200 5,100 200 concentration Chlorination Reaction temperature ° C. 100 100 100 100 100 100 conditions Reaction pressure Mpa 0.40 0.40 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 180 Vortex volume in L 27.2 30.6 0.9 28.8 1.1 1.5 stirring Vortex volume/ L/kg 0.151 0.170 0.005 0.160 0.006 0.008 (PVC + water) (Distance from m/m 0.809 0.970 0.032 0.905 0.040 0.040 liquid surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc-kg .Math. 0.003 0.025 0.005 0.020 0.005 0.004 consumption rate 5 min 200 ppm hydrogen ppm/hr 15 15 15 15 15 15 peroxide Chlorinated Amount of added chlorine mass % 10.6 3.3 17.2 12.2 10.5 10.6 polyvinyl Structure Structural unit (a) mol % 35.6 80.5 1.0 25.4 35.2 35.4 chloride —CH.sub.2—CHCl— resin Structural unit (b) mol % 40.3 8 41.2 35 39 44 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 24.1 11.5 57.8 39.6 25.8 20.6 —CHCl—CHCl— Raman Peak intensity Average 1.254 0.484 2.012 1.368 1.254 1.251 spectroscopic A/B Standard 0.091 0.005 0.079 0.093 0.091 0.092 analysis deviation (Peak average of A/B) + 1.556 0.555 2.293 1.673 1.556 1.554 (Standard deviation).sup.1/2 Molded Sdr 0.0135 0.0035 0.0071 0.0051 0.0108 0.0029 article Residual water droplet x ∘ x x x ∘ Scorch mark (discoloration) x x x x x x Surface shape (unevenness) x ∘ x x x ∘ Continuous productivity (hr) 1.5 2.1 1.9 2 2.3 2 Comparative Examples 7 8 9 10 11 Production Raw material Average degree of polymerization 1000 1000 1000 1000 1000 method PVC Charge amount kg 50 50 50 50 50 Water Ion-exchanged water kg 130 130 130 130 130 Additive ClO.sub.2/Cl.sub.2 ppm 200 200 200 200 200 concentration Chlorination Reaction temperature ° C. 100 100 100 100 100 conditions Reaction pressure Mpa 0.40 0.40 0.40 0.40 0.40 PVC + water kg 180 180 180 180 180 Vortex volume in L 27.2 1.8 1.4 25 26.2 stirring Vortex volume/ L/kg 0.151 0.010 0.008 0.139 0.146 (PVC + water) (Distance from m/m 0.809 0.040 0.052 0.809 0.684 liquid surface to stirring blade)/ Height of liquid surface Average chlorine kg/pvc-kg .Math. 0.016 0.004 0.004 0.016 0.016 consumption rate 5 min 200 ppm hydrogen ppm/hr 15 15 15 15 15 peroxide Chlorinated Amount of added chlorine mass % 10.5 10.6 10.5 10.5 10.3 polyvinyl Structure Structural unit (a) mol % 35.0 35.3 35.2 35.1 35.3 chloride —CH.sub.2—CHCl— resin Structural unit (b) mol % 28 40.5 41 28.5 27 —CH.sub.2—CCl.sub.2— Structural unit (c) mol % 37 24.2 23.8 36.4 37.7 —CHCl—CHCl— Raman Peak intensity Average 1.255 1.256 1.257 1.255 1.254 spectroscopic A/B Standard 0.092 0.095 0.096 0.095 0.097 analysis deviation (Peak average of A/B) + 1.558 1.564 1.567 1.563 1.565 (Standard deviation).sup.1/2 Molded Sdr 0.0033 0.0025 0.0028 0.0035 0.0033 article Residual water droplet ∘ ∘ ∘ ∘ ∘ Scorch mark (discoloration) x x x x x Surface shape (unevenness) Δ ∘ ∘ Δ Δ Continuous productivity (hr) 2.5 3.8 3.5 3.5 3.5

INDUSTRIAL APPLICABILITY

[0140] The present invention can provide a chlorinated polyvinyl chloride resin that enables excellent continuous productivity in molding and that enables a molded article to have both processability and unevenness-preventing properties.