JP2002120224A - Recycling method of glass fiber reinforced thermoplastic resin - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a so-called material recycling method in which glass fiber reinforced thermoplastic resin is re-melted and kneaded and reused, deterioration of mechanical properties due to breakage of glass fiber is suppressed as much as possible, and recycled material is used. A high-concentration of non-recycled material to improve the regeneration rate, and provide a method that can be recycled efficiently and economically. SOLUTION: In the method of remelting and kneading a glass fiber reinforced thermoplastic resin to regenerate, a (A) glass fiber reinforced thermoplastic resin for reproduction, (B) a non-regenerated thermoplastic resin, and (C) a non-regenerated glass. The compounding amounts of the fibers are respectively a, b,
a + b + c = 100, a> 0, b
> 0, c ≧ 0, a / (b + c) <0.8, and (A) a glass fiber reinforced thermoplastic resin for regeneration
A method for recycling a glass fiber reinforced thermoplastic resin, comprising supplying the non-regenerated thermoplastic resin to a process in a molten state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called material recycling method in which a glass fiber reinforced thermoplastic resin is re-melted and kneaded and reused.

[0002]

2. Description of the Related Art Glass fiber reinforced thermoplastic resins are used for many structural parts and functional parts because of their excellent mechanical properties. Recently, there has been a pressing need to promote recycling due to the effective use of resources and the reduction of the burden on the global environment. In many glass fiber reinforced thermoplastic resins, unnecessary parts such as sprues and runners at the time of molding, and those that have completed their product life have been discarded, landfilled, or incinerated. In the case of re-use, the simplest method is a method in which a sprue, a runner, a recovered product, or the like is pulverized, mixed with a non-recycled material at a fixed ratio, and molded. However, in this method, since the recycled material is a crushed product, the supply property to the molding machine and the plasticization property are unstable, which may affect the product quality. In addition, a method of re-melting and kneading unnecessary portions such as sprues and runners and the like to obtain granules, blending them with a non-recycled material at a fixed ratio, and forming the same is also generally performed. However, also in this method, in the case of the glass fiber reinforced thermoplastic resin, during re-melting and kneading, since the glass fiber breakage is large, it is difficult to exhibit the same mechanical properties as the non-recycled material,
It was necessary to minimize the mixing ratio to the non-recycled material so as not to affect the quality.

On the other hand, Japanese Patent Application Laid-Open No. 12-80199 discloses a method of chemically recycling glass fiber reinforced polyamide. However, the method of depolymerizing a molded article or the like to produce a monomer is uneconomical because it requires depolymerization equipment and equipment for separating glass fibers, and requires many steps.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a so-called material recycling method in which a glass fiber reinforced thermoplastic resin is re-melted, kneaded, and reused, so that deterioration of mechanical properties due to breakage of glass fiber is suppressed as much as possible. In addition, it is an object of the present invention to provide a method in which a glass fiber reinforced thermoplastic resin, which is a recycled material, is blended in a high concentration in a non-recycled material, thereby improving a recycling rate and enabling efficient and economical recycling.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, in a method of re-melting and kneading a glass fiber reinforced thermoplastic resin to regenerate, a regenerated material and a non-regenerated material are used. By blending the materials in a specific ratio, and supplying the recycled glass fiber reinforced thermoplastic resin to the process in which the non-regenerated thermoplastic resin is in a molten state, the breakage of the glass fibers can be suppressed, and the mechanical properties The present inventors have found that a recycled material-containing glass fiber reinforced thermoplastic resin with little deterioration can be obtained, and have accomplished the present invention.

That is, the present invention provides: In the method of re-melting and kneading a glass fiber reinforced thermoplastic resin and regenerating, (A) a glass fiber reinforced thermoplastic resin for reproduction, (B)
When the blending amounts of the non-regenerated thermoplastic resin and the (C) non-regenerated glass fiber are respectively a, b, and c parts by weight, a + b + c = 100 a> 0, b> 0, c ≧ 0 a / (b + c) < 0.8, and (A) supplying the recycled glass fiber reinforced thermoplastic resin to the step (B) in which the non-regenerated thermoplastic resin is in a molten state. Recycling method,

[0007] 2. 2. The method for recycling a glass fiber reinforced thermoplastic resin according to the above item 1, wherein the thermoplastic resin is a polyamide. 3. The method for recycling a glass fiber-reinforced thermoplastic resin according to the above item 1, wherein the thermoplastic resin is an aromatic polyester. 2. A glass fiber reinforced thermoplastic resin composition containing a recycled material obtained by the method described in 1 above.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. In the present invention, the glass fiber reinforced thermoplastic resin for recycling is a material to be recycled, and is not particularly limited. However, as long as the object of the present invention is not impaired, it may be a recovered product or may be generated during molding. Unnecessary resin such as a sprue and a runner may be used. However, use environment,
Those that have undergone significant deterioration such as a decrease in molecular weight or discoloration due to the influence of the storage environment and the like are not preferred.

In the present invention, the non-regenerated thermoplastic resin is a thermoplastic resin to be used for mixing and remelting and kneading a recycled glass fiber reinforced thermoplastic resin at a certain ratio, and is substantially a recycled material. It is desirable not to include the same, but as long as the object of the present invention is not impaired, a thermoplastic resin partially obtained by material recycling or a thermoplastic resin obtained by chemical recycling may be contained.

In the present invention, there is no particular limitation on the recycled glass fiber reinforced thermoplastic resin and the non-regenerated thermoplastic resin, and examples thereof include polyethylene resin, polystyrene resin, polypropylene resin, polyamide resin, polyester resin, and polycarbonate resin. , Polyoxymethylene resin, polyphenylene ether resin and the like. Preferred resins are polyamides and aromatic polyesters. Polyamides and aromatic polyesters have a high reinforcing effect by glass fibers.
The glass fiber reinforced resin having a higher glass fiber concentration has a higher breakage of the glass fiber during remelting and kneading. Therefore, the breakage of the glass fiber is suppressed by the recycling method of the present invention. The effect is great. Examples of the polyamide resin include aliphatic polyamides such as polyamide 6, polyamide 11, polyamide 12, polyamide 66, polyamide 610, polyamide 612, and polyamide 46, and these polyamides and terephthalic acid components, isophthalic acid components, and metaxylene range. Aromatic polyamides such as polyamide 6T, polyamide 6I, polyamide MXD6, etc. obtained from amines are exemplified. These polyamides may be used as a homopolymer, may be used by blending the above polyamide, or may be a copolyamide obtained by copolymerizing the above polyamide component. Examples of the aromatic polyester include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate (hereinafter abbreviated as “PTT”), and the like. These aromatic polyesters may be used as a homopolymer, a blend or a copolymer.

The thermoplastic resin of the glass fiber reinforced thermoplastic resin of the present invention and the non-regenerated thermoplastic resin are generally of the same kind, but depending on the purpose, it is not always necessary to use the same thermoplastic resin. good. Further, in the thermoplastic resin of the recycled glass fiber reinforced thermoplastic resin of the present invention, and in the non-regenerated thermoplastic resin, generally used heat stabilizers and antioxidants are used as long as the object of the present invention is not impaired. Additives such as agents, light stabilizers, radical inhibitors, ultraviolet absorbers, nucleating agents, lubricants, release agents, coloring pigments, dyes, and reinforcing agents other than glass fibers.

The glass fibers in the glass fiber reinforced thermoplastic resin for regeneration and the non-recycled glass fibers used in the present invention are not particularly limited, and those usually used for thermoplastic resins can be used. The glass fiber diameter and the chop length of the glass fiber are not particularly limited.
Any of chopped strands, rovings, and milled fibers of ２５25 μm may be used. When using chopped strands, the length is 0.1 to 12m
It can be appropriately selected and used in the range of m.

Further, a material obtained by attaching a generally known silane coupling agent to the surface of glass fiber may be used.
For example, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like are used. it can. Further, as the sizing agent, a glass fiber treated with a known sizing agent such as a urethane resin, a maleic anhydride-modified butadiene resin, a styrene maleic anhydride, or acrylic acid can be used. In general, the same type and amount of glass fiber and non-regenerated glass fiber in the glass fiber reinforced thermoplastic resin for regeneration are used, but depending on the purpose, the type and the amount of blending are different. It may be different.

In the present invention, when the amount of the recycled glass fiber reinforced thermoplastic resin is a part by weight, the amount of the non-regenerated thermoplastic resin is b part by weight, and the amount of the non-regenerated glass fiber is c part by weight. , A + b + c = 100, a> 0, b> 0, c
≧ 0, a / (b + c) <0.8 must be satisfied.
When a / (b + c) is larger than 0.8, it is difficult to suppress breakage of the glass fiber, and deterioration of mechanical properties becomes remarkable.
Preferably, a / (b + c) <0.5.

The recycled glass fiber reinforced thermoplastic resin of the present invention needs to be supplied in a step where the non-regenerated thermoplastic resin is in a molten state. Glass fiber reinforced thermoplastic resin for recycling
When the non-regenerated thermoplastic resin is supplied to the non-molten process,
It becomes difficult to suppress breakage of the glass fiber, and deterioration of mechanical properties becomes remarkable. Glass fiber reinforced thermoplastic resin for recycling
The method for feeding the non-regenerated thermoplastic resin to the process in the molten state is not particularly limited. For example, the non-regenerated thermoplastic resin is supplied from the uppermost stream of a twin-screw extruder, and the non-regenerated heat is supplied downstream of the supply port. A method of supplying a glass fiber reinforced thermoplastic resin for regeneration to a process (site) where the plastic resin is melt-plasticized can be exemplified. When the recycled glass fiber reinforced thermoplastic resin and the non-regenerated thermoplastic resin alone are used, the blended amount of the glass fiber in the regenerated composition is naturally smaller than that of the recycled glass fiber reinforced thermoplastic resin. Depending on the purpose, it may be recycled by this method, but in general, a recycled material having a glass fiber content equal to or more than the glass fiber content of the glass fiber reinforced thermoplastic resin for reproduction is produced. in this case,
From the viewpoint of glass fiber breakage suppression, it is also possible to simultaneously blend non-regenerated glass fibers, but further downstream from the supply position of the above-mentioned recycled glass fiber reinforced thermoplastic resin,
It is desirable to provide non-recycled glass fibers.

The apparatus for carrying out the recycling method of the present invention is not particularly limited.
For example, a single-screw extruder, a twin-screw extruder, a kneader, a Brabender, a plastmill, or the like can be used. However, each apparatus needs to have an apparatus capable of supplying a recycled glass fiber reinforced thermoplastic resin to a portion where the non-regenerated thermoplastic resin is in a molten state. The melt-kneading conditions for carrying out the recycling method of the present invention are not particularly limited, but generally, at a barrel temperature condition higher than the melting point of the thermoplastic resin, the non-regenerated thermoplastic resin is melted, and the glass fiber reinforced thermoplastic resin for regeneration. In the step (site) where is supplied, it is desirable to appropriately set the temperature so that the glass fiber reinforced thermoplastic resin for regeneration is quickly melted. There is no particular limitation on the amount of extrusion, screw configuration, screw rotation speed, die configuration, vent vacuum conditions, but there are conditions such that the glass fibers and non-regenerated glass fibers in the glass fiber reinforced thermoplastic resin for regeneration do not break excessively. desirable.

In the recycling process of the present invention,
If necessary, a heat stabilizer, an antioxidant, a catalyst for recovering the molecular weight, and the like may be added. The present invention will be described below based on examples. The evaluation in Examples and Comparative Examples was performed by the following method. (1) Glass fiber concentration: pellets of the composition are incinerated in a crucible, and the resin component is further ashed at 650 ° C.
From the weight measurement results before and after the incineration, the glass fiber concentration was calculated from the weight of the incinerated material / the weight of the pellet before incineration × 100 (wt%). (2) Mechanical properties: Tensile strength was measured according to ASTM D638, and bending strength and flexural modulus were measured according to ASTM D790.

In the examples and comparative examples, the following thermoplastic resin for regeneration, thermoplastic resin for non-regeneration, and glass fiber were used. (1) Thermoplastic resin for regeneration (A-1) Glass fiber reinforced polyamide 66 resin: Leona 1300G manufactured by Asahi Kasei Corporation Glass fiber concentration 33 wt% (A-2) Glass fiber reinforced PTT resin: P manufactured by Shell
TT resin A glass fiber reinforced PTT resin having a glass fiber concentration of 30% was produced using a twin screw extruder TEM35 manufactured by Toshiba Machine Co., Ltd. using Cortera CP509200 and glass fiber T187 manufactured by Nippon Electric Glass Co., Ltd. (A
For both -1) and (A-2), ASTM D having a thickness of 3 mm was used using an injection molding machine IS-50EP manufactured by Toshiba Machine Co., Ltd.
A test piece conforming to 638 and D790 was obtained, and the test piece, the sprue, and the runner portion were pulverized to an average diameter of about 3 mm with a pulverizer to obtain a thermoplastic resin for regeneration.

(2) Non-regenerated thermoplastic resin (B-1) Polyamide 66 resin: Leona 1300 manufactured by Asahi Kasei Corporation (B-2) PTT resin: Corterra manufactured by Shell Co.
CP509200 (3) Non-recycled glass fiber: (C-1) T275 manufactured by NEC Corporation (for fiber 10 μm polyamide) (C-2) T187 manufactured by NEC Corporation (fiber diameter 13 μm for polyester) )

[0020]

Example 1 (A-1) was used as a recycled glass fiber reinforced thermoplastic resin, (B-1) was used as a non-regenerated thermoplastic resin, and (C-1) was used as a non-regenerated glass fiber. (B-1)
To the same direction twin screw extruder TEM35 (L manufactured by Toshiba Machine Co., Ltd.)
/ D47) from the uppermost stream supply port using a constant weight feeder at a rate of 20 kg / hr, and (B-1) downstream of the extruder.
Is completely melted, (A-1) is side-fed at 30 kg / hr using a constant weight feeder, and further downstream, (C-1) is fed to a 10 kg using a constant weight feeder.
Side feed was performed at kg / hr. The extrusion conditions were a barrel temperature of 290 ° C., a screw rotation number of 300, a degree of vent vacuum of 60 cmHg, and a discharge rate of 60 kg / hr. In addition, the screw configuration is for plasticization of (B-1),
(A-1) A kneading block of L / D 8.5 and a reverse screw of L / D 0.4 are provided upstream of the supply position.
-1) One L / D 0.4 reverse screw is provided downstream of the supply position, and (C-1) L / D is provided downstream of the supply position.
Except for providing one 0.4 reverse screw, only the forward screw was used. The vent port was provided downstream of the (C-1) supply position. The die used had a diameter of 3 mm and an orifice of 4 holes. The molten resin composition extruded from the die was cooled in a cold water bath, and then continuously cut into pellets to obtain a glass fiber reinforced thermoplastic resin. Table 1 shows the evaluation results of the obtained glass fiber reinforced polyamide resin composition. As compared with Comparative Example 1 below, the mechanical properties were excellent, and performance almost equivalent to that of Reference Example 1 was obtained.

[0021]

Example 2 (A-2) was used as a glass fiber reinforced thermoplastic resin for regeneration, (B-2) was used as a non-regenerated thermoplastic resin, and (C-2) was used as a non-regenerated glass fiber. Is supplied at 21 kg / hr, and (A-2) is supplied at 30 kg / hr.
, And a glass fiber reinforced thermoplastic resin was obtained in the same manner as in Example 1, except that (C-2) was side fed at 9 kg / hr. Table 1 shows the evaluation results of the obtained glass fiber reinforced polyester resin compositions. As compared with Comparative Example 2 below, the mechanical properties were excellent, and performance almost equivalent to that of Reference Example 2 described below was obtained.

[0022]

Comparative Example 1 A glass fiber reinforced thermoplastic resin was obtained in the same manner as in Example 1 except that (A-1) and (B-1) were supplied from the uppermost stream of an extruder. Table 1 shows the evaluation results of the obtained glass fiber reinforced polyamide resin composition.

[0023]

Comparative Example 2 A glass fiber reinforced thermoplastic resin was obtained in the same manner as in Example 1 except that (A-2) and (B-2) were supplied from the uppermost stream of an extruder. Table 1 shows the evaluation results of the obtained glass fiber reinforced polyester resin compositions.

[0024]

Comparative Example 3 54 kg / hr of (A-1), (B-1)
4.02 kg / hr, (C-1) 1.98 kg / hr
A glass fiber reinforced thermoplastic resin was obtained in the same manner as in Example 1 except that r was supplied. Table 1 shows the evaluation results of the obtained glass fiber reinforced polyamide resin composition.

[0025]

Reference Examples 1 and 2 Reference Examples 1 and 2 are also shown in Table 1. Reference Examples 1 and 2 are (A-1) and (A
Without reproducing the equivalent of (-2), (B-
1) and (C-1), and (B-2) and (C-2), which were evaluated.

[0026]

[Table 1]

[0027]

According to the present invention, in a so-called material recycling method in which a glass fiber reinforced thermoplastic resin is re-melted and kneaded and reused, deterioration of mechanical properties due to breakage of glass fiber is suppressed as much as possible and non-recycling is performed. It can be efficiently and economically recycled by blending it at a high concentration in the material, improving the recycling rate.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // B29K 105: 12 B29K 105: 12 105: 26 105: 26 F term (reference) 4F070 AA47 AA54 AB09 AB26 AC28 AD02 AE01 FA03 FB06 FC05 4F301 AA25 AA27 AA30 AB01 AB03 AD09 AD10 BC26 BC36 BC40 BC63 BC71 BC75 BD11 BD31 BD36 BD42 BD44 BF16 BF32 4J002 CF041 CF061 CF071 CL001 CL011 CL021 CL031 DL006 FA046 FD016

Claims (4)

[Claims] 1. A method for remelting and kneading a glass fiber reinforced thermoplastic resin to regenerate, wherein (A) a glass fiber reinforced thermoplastic resin for regeneration, (B) a non-regenerated thermoplastic resin, and (C) a non-regenerated thermoplastic resin. The amounts of the glass fibers are respectively a, b,
a + b + c = 100 a> 0, b> 0, c ≧ 0 a / (b + c) <0.8, and (A) the recycled glass fiber reinforced thermoplastic resin is (B) A method for recycling a glass fiber reinforced thermoplastic resin, wherein the method supplies the non-regenerated thermoplastic resin to a step in which the thermoplastic resin is in a molten state. 2. The method for recycling a glass fiber reinforced thermoplastic resin according to claim 1, wherein the thermoplastic resin is a polyamide. 3. The method for recycling a glass fiber reinforced thermoplastic resin according to claim 1, wherein the thermoplastic resin is an aromatic polyester. 4. A glass fiber reinforced thermoplastic resin composition containing a recycled material obtained by the recycling method according to claim 1.