JP3144694B2 - Manufacturing method of polycarbonate resin molding material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polycarbonate resin molding material, which uses a specific corrosion-resistant and abrasion-resistant material as a molten resin filter for an extruder to suppress the generation of dust by the filter. It relates to a manufacturing method.

[0002]

2. Description of the Related Art As a method for producing a molding material from a polycarbonate resin solution, a resin is separated from the solution,
A method of drying and pelletizing with an extruder is used.

[0003] This method is preferable in view of the size of the production apparatus and the processing efficiency, but since the extrusion of the aromatic polycarbonate resin is performed under high temperature conditions, a part of the raw material is thermally decomposed,
It was thought that the formation of gels and carbides was inevitable. In addition, when the extrusion is once stopped and then restarted, when the operation is stabilized after the start of the extrusion and the generation of dust due to the formation of a gelled material or a carbide is reduced to a predetermined amount or less, 10 hours or more. Time was required, and the production efficiency was significantly deteriorated.

[0004] In order to suppress an increase in dust due to the extrusion operation, there is a method in which a filter is inserted into an extruder and dust in the molten resin is captured by the filter in some cases. However, some filters cannot effectively reduce dust. In addition, from the recognition that the increase in dust caused by the extruder is a problem exclusively related to the stability of the polycarbonate resin, a method of adding a stabilizer to the polycarbonate resin in the past to reduce the increase in dust in the extrusion process has been proposed. Various attempts have been made, but are not a complete solution.

[0005]

The inventors of the present invention have conducted a study including a filter in order to reduce dust, and as a result, the resin remaining in the filter portion is liable to burn or gel, and the filter is liable to generate dust. The present invention was found to be a cause of the problem, and that the generation of dust by the filter was substantially suppressed when a specific material was used.

That is, the present invention relates to a method for producing a polycarbonate molding material by melt-extruding a polycarbonate resin material powder, wherein a molten resin filter of an extruder is formed of a corrosion-resistant and wear-resistant alloy comprising the following alloy components. A method for producing a polycarbonate resin molding material characterized by substantially suppressing generation of dust by a filter using an extruder having a molten resin filter Alloy component Ni: 40 to 65% by weight Cr: 10 to 30% by weight Mo : 8 to 20% by weight W: 0.1 to 5% by weight Fe: 1 to 20% by weight Co: 0 to 3% by weight V: 0 to 0.5% by weight Remainder: unavoidable impurities.

In the present invention, the polycarbonate resin is
An aromatic polycarbonate resin produced by using a dihydric phenol as a monomer and linking a dihydric phenol with a carbonic ester by a phosgene method, a transesterification method, a pyridine method, or the like, and most commonly bisphenol A [= 2,2 -
Bis (4-hydroxyphenyl) propane, hereinafter referred to as BPA. ] As a monomer, but also includes a transparent resin such as a graft copolymer of the polycarbonate and another resin. In the present invention, the aromatic polycarbonate resin powder, after separating the polycarbonate resin solution from the polymerization solution and purification, further fine filtration, centrifugation, etc., to remove fine dust, a purified solvent solution of the purified polycarbonate resin good solvent, obtain. Next, a method of concentrating and gelling the resin solution obtained by adding this solution as it is or by adding a poor solvent to such an extent that precipitation does not occur (“gel concentration method”: gelation by solvent evaporation, flash concentration gelation, etc.) "Concentration method", which is a "warm water dropping method" in which the resin solution is dropped into warm water to evaporate the solvent and gels, and the resin solution is dropped into the poor solvent or the poor solvent is dropped into the resin solution A dry powder obtained by separation and drying by a method such as “precipitation method”; or a warming powder obtained by a “hot water dropping method”,
Alternatively, it is a wet powder produced by a method in which water is added to the powder obtained by the precipitation method, and the solvent is distilled off by heating while appropriately performing wet grinding. A method in which the wet powder is introduced into an extruder in which volatile components can be easily removed from the vent portion and the solvent is distilled off together with the extrusion is preferable because there is no increase in dust in the drying step.

In the present invention, various extruders such as a single-screw extruder, a vent-type extruder, a multi-screw extruder, and a special extruder can be used. The components of the alloy of the resin filter used in the present invention are: Ni: 40 to 65% by weight, preferably 50 to 65% by weight; Cr: 10 to 30% by weight, preferably 15 to 25% by weight; Mo: 8 to 20% by weight. ,
W: 0.1 to 5% by weight, preferably 2 to 5% by weight; Fe: 1 to 20% by weight, preferably 1 to 7% by weight; Co: 0 to 3% by weight;
V: 0 to 0.5% by weight; balance: unavoidable impurities (total 100% by weight). For example, Hastelloy C [C 0.
08 wt% or less, Si 1.00 wt% or less, Mn 1.00 wt% or less, Ni residue, Cr 14.50-16.50 wt%, Mo 15.00-17.00 wt%, Fe 4.00-7.00 wt%, W 3.00-4.50 wt%, V0 .
35% by weight or less (Hastelloy C catalog); Ni residue, Cr 1
6% by weight, Mo 16% by weight, W 4% by weight, Fe 5% by weight
("Chemical Equipment", July 1990, page 72, Table 1, "Representative Chemical Components of Various Ni-Cr-Mo Alloys")], Hastelloy C-276
[Ni remaining, Co 2.5 wt% or less, Cr 14.5-16.5 wt%, Mo
15.0-17.0% by weight, W 3.0-4.5% by weight, Fe 4.0-7.0% by weight, Si 0.08% by weight or less, Mn 1.0% by weight or less, C 0.02% by weight or less, V 0.35% by weight or less, P 0.04% by weight or less , S0.0
3% by weight or less (Catalog of Hastelloy C-276); Ni
Remaining, Cr 16% by weight, Mo 16% by weight, W 4% by weight, Fe 5
% By weight, others (Low C, Si) (Chemical equipment table 1)
], Hastelloy C-22 [C 0.015% by weight or less, S
i 0.08 wt% or less, Mn 0.50 wt% or less, P 0.02 wt% or less, S 0.02 wt% or less, Ni balance, Cr 20.0-22.5 wt%, Mo 12.5-14.5 wt%, Fe 2.0-6.0 wt%, Co 2.5% by weight or less, V 0.35% by weight or less, W 2.5-3.5% by weight ("Steel JIS Handbook", page 1823); Ni balance, Cr 22% by weight, Mo 13% by weight, W 3% by weight, Fe 3% by weight, Other
(Ti, Low C, Si) (the above-mentioned "Chemical equipment" Table 1)], Hastelloy X [C 0.05-0.15% by weight, Si 1.00% by weight or less, Mn
1.00% by weight or less, P 0.040% by weight or less, S 0.030% by weight or less, Ni residue, Cr 20.5-23.0% by weight, Mo 8.0-10.0% by weight, Fe 17.0-20.0% by weight, Co 0.5-2.5% by weight, W 0.20% -
1.0 wt% (Steel JIS Handbook); Ni residue, Co
0.50-2.50 wt% or less, Cr 20.50-23.00 wt%, Mo 8.0
0-10.00 wt%, W 0.20-1.00 wt%, Fe 17.00-20.00
Wt%, C 0.05-0.15 wt%, Si 1.00 wt% or less, Mn
1.0 wt% or less, B 0.010 wt% or less, P 0.040 wt%
Below, S 0.030% by weight or less (Catalog of Hastelloy X)
]. Hastelloy is a trade name (registered trademark).

The nominal filtration diameter of the filter is usually 1 to 10
0 μm, preferably 30 to 60 μm. Examples of the filter include various types such as a disk filter, a leaf disk filter, a cylindrical filter, and a tube type filter, and a leaf disk filter and a disk filter are particularly preferable. The filter medium is desirably a metal fiber sintered body in which the alloy fiber is formed into a nonwoven fabric and the nonwoven fabric is sintered to form a porous body.

Hereinafter, the present invention will be described with reference to examples and the like.
In the measurement of the number of dusts in Examples and the like, a solution in which 1 g of a polycarbonate resin was dissolved in 100 cc of methylene chloride was measured using a light scattering type particle size sensor. Also,
The presence of burnt pellets was confirmed visually. APHA was measured by visually comparing the resin solution with an APHA standard solution,
According to the method of calculating the APHA number. In addition, APHA
Standard solution is 1.245 g of special grade potassium dichloroplatinate reagent
And 1.000 g of cobalt chloride reagent, 100 m hydrochloric acid
The resulting solution was dissolved in 1 l and distilled water was added to 1000 ml to give a standard current solution of APHA No. 500, which was then diluted to prepare the APHA standard solution.

[0011]

【Example】

Example 1, Comparative Example 1 As a molten resin filter, a Hastelloy C-22 alloy having a nominal filtration diameter of 40 μm (58.8% by weight of Ni, Cr21.
3% by weight, Mo 12.9% by weight, W 3.1% by weight, Fe
3.6% by weight, 0.1% by weight of Co, 0.03% by weight of V,
Other unavoidable impurities) Polycarbonate resin powder (0.5 μm or more, 30,000 dusts / g) is extruded at a high temperature (330 ° C. or 350 ° C.) using a filter, the number of dusts in the pellets is measured, and the The increase was determined. For comparison, stainless steel (SUS31)
6) Except for using a filter, the amount of dust increase due to extrusion was determined in the same manner. Table 1 compares the results.

Table 1 Amount of dust increase by extrusion (pieces / g) Example 1 Comparative Example 1 Extrusion temperature Hastelloy filter SUS filter 330 ° C 2,000 pieces 8,000 pieces 350 ° C 5,000 pieces 12,000 pieces The amount of dust increase due to extrusion shown includes the amount of increase due to factors other than the filter. Therefore, when the amount of dust increase in Example 1 and Comparative Example 1 is compared, the use of the Hastelloy filter of the present invention reduces the generation of dust by the filter. It can be seen that it is greatly suppressed.

Example 2, Comparative Example 2 Using the same Hastelloy filter as in Example 1 (Example 2) or the same SUS filter as in Comparative Example 1 (Comparative Example 2),
The polycarbonate resin is heated at a normal extrusion temperature (280 to 30).
0 ° C.) and a high temperature (330 ° C. or 350 ° C.), and extruded into pellets (0.02 pellets per piece).
g, 100,000 pieces (2 kg), and the mixing ratio (pieces / 2 kg) of the burnt pellets was measured. Burnt pellets were confirmed visually. The results are shown in Table 2.

Table 2 Burnt pellet mixing rate (pieces / 2 kg) Example 2 Comparative Example 2 Extrusion temperature Hastelloy filter SUS filter 300 ° C. 0 pieces 2 330 ° C. 0 pieces 10 pieces 350 ° C. 0 pieces 60 pieces Example 2 of Table 2 Comparing the burnt pellet mixing rates of Comparative Example 2 and Comparative Example 2, it can be seen that the use of the Hastelloy filter of the present invention significantly reduces the generation of burnt pellets.

Example 3 4.0 g of a polycarbonate resin powder dried at 120 ° C. for 4 hours and a Hastelloy X alloy (Ni 47.36)
Wt%, Cr 23.49 wt%, Mo 8.80 wt%,
W 0.7% by weight, Fe 18.84% by weight, Co 0.64
Wt.%, Other unavoidable impurities) and a molten resin filter (10 mm × 10 mm) with a nominal filtration aperture of 40 μm
× 1 mm) in a test tube, and each was prepared in a nitrogen stream at (A) 280 ° C. for 20 hours and (B) 300 hours.
5 ° C., (C) 320 ° C., 2 hours, (D) 340
C. for 1 hour. Next, each content was dissolved in purified methylene chloride to make a 25 ml solution, and the APHA of this solution was measured. Table 3 shows the results.

Comparative Example 3 SUS316L alloy (Ni 12.06% by weight, Cr 1
6.24 wt%, Mo 2.02 wt%, C 0.013 wt%, Si 0.29 wt%, Mn 0.73 wt%, residual F
e and unavoidable impurities). Table 3 shows the results. Comparative example 4 It carried out similarly to Example 3 except not using a fusion filter. Table 3 shows the results.

Table 3 Example 3 Comparative Example 3 Comparative Example 4 Melting Conditions Attachment to Metal Surface Temperature Attachment to Metal Surface Time State of APHA Resin APHA Resin APHA 280 ° C 2 hr 40 No change 250 No change 30 300 ° C 5 hr 30 No change 200 Resin foam 20 320 ℃ 2 hr 40 No change 450 Brown gel formation 30 Resin foam 340 ℃ 1 hr 30 No change 450 Brown gel formation 20 Resin foam

[0018]

According to the present invention, generation of dust by the filter can be substantially suppressed. Since dust is not increased by the filter according to the present invention, the present invention can of course be used for producing a polycarbonate resin molding material for optical use.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Tadashi Okajima, 4-7-17-1 Ikenomiya, Hirakata City, Osaka Prefecture Nihon Seisen Co., Ltd. Inside the Hirakata Plant No.2, 7 Nippon Seisen Co., Ltd. Examiner Tomoya Kato (56) References JP-A-64-75653 (JP, A) JP-A-4-97819 (JP, A) JP-A-1-159229 ( JP, A) JP-A-59-76328 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 47/00-47/96 B29B 7/00-7/94 B29B 9 / 06

Claims (2)

(57) [Claims] 1. A method for producing a polycarbonate molding material by melt-extruding a raw material powder of a polycarbonate resin, wherein the molten resin filter is formed of a Ni—Cr—Mo alloy comprising the following alloy components as a molten resin filter of an extruder. A method for producing a polycarbonate resin molding material characterized in that the generation of dust by a filter is substantially suppressed using an extruder having an alloy component: Ni: 40 to 65% by weight Cr: 10 to 30% by weight Mo: 8 to 20% by weight W: 0.1 to 5% by weight Fe: 1 to 20% by weight Co: 0 to 3% by weight V: 0 to 0.5% by weight Remainder: inevitable impurities 2. The method according to claim 1, wherein the Ni—Cr—Mo alloy is Hastelloy C, Hastelloy C-276, Hastelloy C-22, or Hastelloy X.