KR20030092576A - A thermosetting recyclic resin - Google Patents

A thermosetting recyclic resin Download PDF

Info

Publication number
KR20030092576A
KR20030092576A KR1020020030282A KR20020030282A KR20030092576A KR 20030092576 A KR20030092576 A KR 20030092576A KR 1020020030282 A KR1020020030282 A KR 1020020030282A KR 20020030282 A KR20020030282 A KR 20020030282A KR 20030092576 A KR20030092576 A KR 20030092576A
Authority
KR
South Korea
Prior art keywords
resin
thermosetting
smc
filler
waste
Prior art date
Application number
KR1020020030282A
Other languages
Korean (ko)
Inventor
최치훈
박상선
Original Assignee
현대자동차주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 현대자동차주식회사 filed Critical 현대자동차주식회사
Priority to KR1020020030282A priority Critical patent/KR20030092576A/en
Publication of KR20030092576A publication Critical patent/KR20030092576A/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K11/00Use of ingredients of unknown constitution, e.g. undefined reaction products
    • C08K11/005Waste materials, e.g. treated or untreated sewage sludge
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08JWORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2300/00Characterised by the use of unspecified polymers
    • C08J2300/24Thermosetting resins
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00Specific properties of additives
    • C08K2201/002Physical properties
    • C08K2201/003Additives being defined by their diameter

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

PURPOSE: A thermosetting recycled resin is provided, to obtain a recycled resin showing favorable mechanical properties by using the waste SMC (sheet molding compound) pulverized one without using additional separation processes of a resin, glass fiber and a filler. CONSTITUTION: The thermosetting recycled resin comprises an unsaturated polyester-based base resin; and 2-20 wt% of the waste SMC one having an average diameter of 0.05-0.3 mm as an auxiliary filler.

Description

열경화성 재생수지{A thermosetting recyclic resin}Thermosetting Recycling Resin

본 발명은 열경화성 수지에 관한 것으로서, 보다 상세하게는 불포화 폴리에스테르 계통의 기초 수지에다 평균직경이 0.05 ~ 0.3 mm 인 폐 SMC 분쇄물 2 ~ 20 중량%를 보조 충진제로 배합하되 별도의 수지, 유리 섬유 또는 충진제 분리과정 없이 상기 폐 SMC(Sheet Molding Compound) 분쇄물을 사용하는 것을 특징으로 하는 열경화성 재생수지에 관한 것이다.The present invention relates to a thermosetting resin, and more particularly, to 2 to 20% by weight of a waste SMC pulverized product having an average diameter of 0.05 to 0.3 mm and an auxiliary filler, and a separate resin and glass fiber. Or it relates to a thermosetting recycled resin, characterized in that using the waste SMC (Sheet Molding Compound) pulverized product without a filler separation process.

종래에 주로 트럭이나 버스와 같은 상용차의 차체 외판으로 사용되고 있는 SMC 재료는 통상 25.4 mm 의 길이로 절단된 유리섬유가 보강제로 사용된다. 아울러 제품의 구조 강성 및 치수 안정성 등 기계적 물성을 확보하고, 재료비를 절감을 위하여 원료 수지에다 무기 충진제( Mineral filler )를 배합 한다. 이때 무기 충진제로는 탄산 칼슘이 많이 사용되고, 특히 자동차용 SMC 재료인 경우에는 보통 직경이 0.01 ~ 0.05 mm 인 제품이 주로 사용된다.Conventionally, SMC material, which is mainly used as a body shell of a commercial vehicle such as a truck or a bus, is usually used as a reinforcing agent, glass fiber cut to a length of 25.4 mm. In addition, in order to secure mechanical properties such as structural rigidity and dimensional stability of the product, and to reduce the material cost, the inorganic filler is mixed with the raw material resin. In this case, as the inorganic filler, calcium carbonate is used a lot, and in the case of automobile SMC materials, products having a diameter of usually 0.01 to 0.05 mm are mainly used.

그런데 일반적으로 열경화성 수지는 열가소성 수지에 비하여 재생이 매우 곤란하여 폐기물은 주로 매립 또는 소각 처리된다. 특히, SMC공법으로 제조되는열경화성 수지의 경우, 원료수지의 함량은 약 30 중량%에 불과하고 유리섬유나 무기충전제 등의 함량이 약 70 중량%나 되기 때문에 이를 원료수지 형태로 회수하는 것은 효율성 측면에서 매우 불리한 실정이었다. 따라서 열경화성 수지, 특히 SMC 수지를 효과적으로 재생할 수 있는 방법에 대한 개발이 요구되어 왔다.However, in general, thermosetting resins are more difficult to recycle than thermoplastic resins, and waste is mainly buried or incinerated. In particular, in the case of the thermosetting resin manufactured by the SMC method, the content of the raw material resin is only about 30% by weight and the content of glass fiber or inorganic filler is about 70% by weight, so recovering it in the form of the raw material is an efficiency aspect. Was very unfavorable. Therefore, development of a method for effectively regenerating thermosetting resins, particularly SMC resins, has been required.

이에, 본 발명의 발명자들은 상기의 문제점을 해결하기 위한 노력의 일환으로 열경화성 수지를 제조 할 때, 기존 무기 충진제의 일부를 폐 SMC 분쇄물로 대체 하되 재생수지의 기계적 물성을 적정 수준으로 유지시킬 수 있는 배합비율을 개발하므로서 본 발명을 완성하게 되었다.Therefore, the inventors of the present invention, when manufacturing the thermosetting resin in an effort to solve the above problems, can replace some of the existing inorganic fillers with the waste SMC pulverized, but can maintain the mechanical properties of the recycled resin to an appropriate level The present invention was completed by developing a compounding ratio.

따라서, 본 발명은 폐 SMC 분쇄물을 보조 충진제로 사용한 열경화성 재생수지를 제공하는데 그 목적이 있다.Accordingly, an object of the present invention is to provide a thermosetting recycled resin using waste SMC crushed powder as an auxiliary filler.

본 발명은 열 경화성 수지를 제조함에 있어서, 불포화 폴리에스테르 계통의 기초 수지에 크기가 0.05 ~ 2 mm 인 폐 SMC 분쇄물 2 ~ 20 중량%를 보조 충진제로 배합하는 열경화성 재생수지를 특징으로 한다.The present invention is characterized in that the thermosetting resin is prepared by mixing 2 to 20% by weight of the waste SMC pulverized product having a size of 0.05 to 2 mm with the auxiliary filler in the base resin of the unsaturated polyester system.

이하, 본 발명을 더욱 상세히 설명하면 다음과 같다.Hereinafter, the present invention will be described in more detail.

본 발명에 따른 열경화성 재생수지의 제조방법에서는 기초수지( Matrix )인 불포화 폴리에스테르 계통의 수지에다 섬유형태의 보강제, 무기충진제 및 보조 충진제를 배합한다. 이때, 보강제는 종래에 사용되고 있는 것을 사용하고, 무기 충진제는 탄산칼슘, 운모, 탈크, 점토 등을 하나 또는 둘 이상 조합하여 사용한다.In the method for producing a thermosetting regenerative resin according to the present invention, a fiber-type reinforcing agent, an inorganic filler, and an auxiliary filler are blended with an unsaturated polyester resin that is a matrix resin. At this time, the reinforcing agent is used conventionally, and the inorganic filler is used in combination of one or two or more calcium carbonate, mica, talc, clay and the like.

본 발명의 특징인 보조 충진제로는 성형공정 또는 조립공정에서 회수한 폐 SMC 분쇄물을 사용한다. 폐 SMC 분쇄물은 먼저 전기 톱 등의 절단기를 사용하여 100 × 200 mm 정도의 크기로 절단하고, 분쇄기 및 밀링 장치를 사용하여 미세한 분말상으로 분쇄하되, 먼저 분쇄기로 5 ∼ 20 mm 크기로 1차 분쇄하고 다시 고속 밀링 장치로 0.05 ∼ 0.3 mm의 크기로 미세하게 분쇄하여 일반적으로 사용되는 무기충전제와 혼합하여 사용한다. 이 때 재생 열경화성 수지조성물의 기계적물성은 분쇄물의 입자 크기와 더불어 분산 정도에 영향을 받게 된다. 즉, 입자크기가 0.5mm 이상으로 크면 무기충전제와의 혼합도 잘 되지 않고 아울러 배합시에도 불포화 폴리에스테르 수지 및 유리섬유와의 분산성이 나빠져 물성감소의 요인으로 작용할 수 있다. 그러므로 보조충전제로 사용되는 폐 SMC 분쇄물의 크기가 적을수록 유리하나, 아주 미세하게 분쇄할 수 있는 밀링 장치를 사용할 경우 처리비용이 증가하고 작업성이 나빠진다는 단점이 있으므로 적절한 크기의 선정이 중요하다. 한편 SMC 의 배합 공정에서 일반 무기충전제와 보조 무기충전제를 미리 혼합시켜 불포화 폴리에스테르 수지에 교반시켜 원료액에 분산된 상태로 투입되므로 최종 수지조성물내에서의 분산성도 충분히 확보될 수 있다.As a secondary filler which is a feature of the present invention, the waste SMC pulverized product recovered in the molding process or the assembly process is used. The waste SMC pulverized product is first cut to a size of about 100 × 200 mm using a cutting machine such as a chainsaw, and ground into fine powder using a pulverizer and a milling apparatus. And then finely pulverized to a size of 0.05 ~ 0.3 mm with a high-speed milling device is used by mixing with commonly used inorganic fillers. In this case, the mechanical properties of the regenerated thermosetting resin composition are affected by the degree of dispersion along with the particle size of the pulverized product. That is, when the particle size is larger than 0.5 mm, the mixing with the inorganic filler is difficult, and the dispersibility between the unsaturated polyester resin and the glass fiber is worse even during blending, which may act as a factor of reducing the physical properties. Therefore, the smaller the size of the waste SMC pulverized product used as an auxiliary filler is advantageous, but when using a milling device that can be pulverized very fine, there is a disadvantage that the processing cost increases and the workability worsens, so it is important to select an appropriate size. Meanwhile, in the blending process of SMC, the general inorganic filler and the auxiliary inorganic filler are mixed in advance and stirred in an unsaturated polyester resin to be added in a dispersed state in the raw material solution, thereby ensuring sufficient dispersibility in the final resin composition.

보조 충진제인 폐 SMC의 함량은 수지 전체에 대하여 2 ~ 20 중량%가 되도록 하여 일반적인 SMC 배합 공정에 따라 배합한다. 이때, 수지의 재활용율을 높이기 위해서 가능하면 폐 SMC 분쇄물의 함량이 많도록 하는 것이 유리 하지만 폐SMC 분쇄물 자체의 탄성율( Bulk modulus )은 어차피 일반 무기 충진제 보다 낮을 수 밖에 없기 때문에 그 함량이 20 중량% 를 초과하게 되면 제조된 재생수지의 굴곡 탄성율 등 기계적 물성이 감소하게 될 우려가 있다.The content of waste SMC, which is a secondary filler, is 2 to 20% by weight based on the total resin, and is blended according to a general SMC compounding process. At this time, in order to increase the recycling rate of the resin, it is advantageous to increase the content of the waste SMC powder as much as possible, but since the bulk modulus of the waste SMC powder itself is inevitably lower than that of the general inorganic filler, the content is 20 weight. When the percentage is exceeded, mechanical properties such as flexural modulus of the produced recycled resin may be reduced.

본 발명에서 보조 충진제로 사용하는 폐 SMC 분쇄물의 내부에는 이미 유리섬유나 무기 충진제를 포함 하고 있기 때문에 보조 충진제의 함량에 따라 무기 충진제의 함량이 조절 되는데 보조 충진제와 무기 충진제를 합한 충진제 전체의 함량이 40 ~ 60 중량%가 되도록 한다. SMC 분쇄물은 주성분이 기초수지와 화학적으로 동일한 성분인 불포화 폴리에스테르로 이루어져 있기 때문에 이들을 서로 배합 할 때, 별도로 표면처리를 하지 않아도 충분한 접착력을 얻을 수 있다.In the present invention, since the waste SMC pulverized product used as the auxiliary filler already contains glass fiber or an inorganic filler, the content of the inorganic filler is controlled according to the content of the auxiliary filler, but the content of the entire filler combined with the auxiliary filler and the inorganic filler is increased. 40 to 60% by weight. Since the SMC pulverized product is composed of unsaturated polyester whose main component is chemically identical to that of the basic resin, when the compounds are blended with each other, sufficient adhesive strength can be obtained without any surface treatment.

이하, 실시예에 의거하여 본 발명을 더욱 구체적으로 설명하겠는바, 본 발명이 다음 실시예에 의하여 한정되는 것은 아니다.Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by the following Examples.

비교예 1Comparative Example 1

다음 표 1과 같은 성분 및 조성비에 따라 배합하되 불포화 폴리에스테르 수지 MP3941(세원화성)를 기초 수지로 사용하고, 실험실용 일반 SMC 배합기를 이용하여 약 100 kg의 쉬트(sheet) 상태의 시료를 제조하였다. 약 45℃의 온도에서 3일간 증점시킨 후 500 Ton Press 를 이용하여 두께가 2.5 mm 인 평판 형태의 성형품을 얻었다.Next, according to the ingredients and composition ratios shown in Table 1, but using an unsaturated polyester resin MP3941 (sewonhwa) as the base resin, a sample of about 100 kg sheet (sheet) state was prepared using a laboratory general SMC blender. . After thickening at a temperature of about 45 ° C. for 3 days, a molded article having a thickness of 2.5 mm was obtained using a 500 Ton Press.

이때, 보강제로는 유리섬유( P 203, Vetrotex )를 25.4mm 길이로 잘라 사용하였고, 무기 충진제로서 탄산칼슘( FC 700, 우진화학 )을 사용하였다.At this time, the glass fiber (P 203, Vetrotex) was cut into 25.4mm length as a reinforcing agent, and calcium carbonate (FC 700, Woojin Chemical) was used as the inorganic filler.

비교예 2, 3Comparative Examples 2 and 3

상기 비교예 1과 동일한 조건에서 시료를 제조하였다. 불포화 폴리에스테르 수지는 MP3941(세원화성)을 그대로 사용하였고 저수축제로서 LPV-40(애경화학 )을 추가로 사용 하였다. 보강제 및 유리섬유는 비교예 1과 동일한 종류를 사용하였다.Samples were prepared under the same conditions as in Comparative Example 1. As the unsaturated polyester resin, MP3941 (Sewon Hwaseong) was used as it was, and LPV-40 (Aekyung Chemical) was additionally used as a low shrinkage agent. As the reinforcing agent and glass fiber, the same kind as in Comparative Example 1 was used.

실시예 1 ∼ 5Examples 1-5

상기 비교예 1과 같은 동일한 방법으로 다음 표 1의 조성비에 따라배합하되, 무기 충진제와 함께 폐 SMC 분쇄물을 각 실시예 별로 2.5, 5.0, 7.5, 10.0, 12.5 중량% 포함되도록 하고, 전체 충진제의 함량은 46 중량%가 되도록 하였다. 보조충전제로 사용된 분쇄물의 경우 우선 일반적으로 사용되는 무기충전제와 고속 혼합기(Mixer)로 충분히 혼합하여 SMC 배합과정의 원료액 제조 혼합기에 투입되도록 한다.In the same manner as in Comparative Example 1, according to the composition ratio of the following Table 1, but including the inorganic filler waste SMC pulverized in each example to include 2.5, 5.0, 7.5, 10.0, 12.5% by weight, of the total filler The content was set to 46% by weight. In the case of the pulverized product used as the auxiliary filler, the inorganic filler and the high speed mixer (Mixer) are generally mixed sufficiently to be introduced into the raw material liquid preparation mixer of the SMC compounding process.

실시예 6 ∼ 8Examples 6-8

상기 비교예 3과 같은 동일한 방법으로 다음 표 1의 조성비에 따라 배합하였으며, 무기 충진제와 함께 폐 SMC 분쇄물을 각각 2.5, 5.0, 10 중량% 포함되도록 하고, 마찬가지로 전체 충진제의 함량은 46 중량%가 되도록 하였다.In the same manner as in Comparative Example 3 was formulated according to the composition ratio of the following Table 1, to include the waste SMC pulverized powder with inorganic fillers, respectively, 2.5, 5.0, 10% by weight, and the content of the total filler is 46% by weight It was made.

상기 실시예 및 비교예에 따라 제조된 시편에 대하여 다음과 같은 방법으로 기계적 물성을 시험하고, 그 결과를 다음 표 2에 나타내었다.The mechanical properties of the specimens prepared according to the Examples and Comparative Examples were tested in the following manner, and the results are shown in Table 2 below.

1) 비중 : ASTM 7921) Specific gravity: ASTM 792

2) 굴곡 탄성율 및 굴곡강도 : ASTM 790, W = 25 mm × L = 75 mm,2) Flexural modulus and flexural strength: ASTM 790, W = 25 mm × L = 75 mm,

Cross - head Speed = 1.3 mm/minCross-head Speed = 1.3 mm / min

3) 인장 탄성율 및 인장강도 : ASTM 638, Type I ,3) Tensile modulus and tensile strength: ASTM 638, Type I,

Cross - head Speed = 5 mm/minCross-head Speed = 5 mm / min

4) 충격강도 : ASTM D256( Izod Type )4) Impact Strength: ASTM D256 (Izod Type)

이상의 결과로부터 알 수 있는 바와 같이, 본 발명에 따르면 폐 SMC 분쇄물을 이용한 재생 수지임에도 불구하고 정상적인 수지에 비해 인장강도 등 각종 기계적 물성이 약 20 %의 범위 이내의 수준을 유지하는 재생수지를 제조할 수 있다. 본 발명에 따라 제조된 재생수지는 차체 부품 중 내판( Inner panel )의 소재로 사용할 경우 보다 효과적이다.As can be seen from the above results, according to the present invention, despite the recycled resin using waste SMC pulverized products, the recycled resin is maintained in the range of about 20% of various mechanical properties such as tensile strength, compared to the normal resin. can do. The recycled resin produced according to the present invention is more effective when used as a material of the inner panel of the vehicle body parts.

Claims (1)

불포화 폴리에스테르 계통의 기초 수지에 평균직경이 0.05 ~ 0.3 mm 인 폐 SMC 분쇄물 2 ~ 20 중량%를 보조 충진제로 포함하는 것을 특징으로 하는 열경화성 재생수지.A thermosetting regenerative resin, comprising 2 to 20% by weight of waste SMC pulverized product having an average diameter of 0.05 to 0.3 mm as an auxiliary filler in an unsaturated polyester base resin.
KR1020020030282A 2002-05-30 2002-05-30 A thermosetting recyclic resin KR20030092576A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020020030282A KR20030092576A (en) 2002-05-30 2002-05-30 A thermosetting recyclic resin

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020020030282A KR20030092576A (en) 2002-05-30 2002-05-30 A thermosetting recyclic resin

Publications (1)

Publication Number Publication Date
KR20030092576A true KR20030092576A (en) 2003-12-06

Family

ID=32385152

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020020030282A KR20030092576A (en) 2002-05-30 2002-05-30 A thermosetting recyclic resin

Country Status (1)

Country Link
KR (1) KR20030092576A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR960017739A (en) * 1994-11-18 1996-06-17 유현식 Manufacturing method of BMC or BMC using EMC waste as filler
JPH09234802A (en) * 1996-02-29 1997-09-09 Mitsubishi Plastics Ind Ltd Fiber-reinforced resin molding
JPH1158376A (en) * 1997-08-26 1999-03-02 Kubota Corp Frp molding material composition
JPH11188724A (en) * 1997-12-26 1999-07-13 Daikyo Inc Resin molding material, resin molded article and resin molding method using the same
KR20010008243A (en) * 2000-11-17 2001-02-05 이종철 The method and its products of used polyuretane foam

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR960017739A (en) * 1994-11-18 1996-06-17 유현식 Manufacturing method of BMC or BMC using EMC waste as filler
JPH09234802A (en) * 1996-02-29 1997-09-09 Mitsubishi Plastics Ind Ltd Fiber-reinforced resin molding
JPH1158376A (en) * 1997-08-26 1999-03-02 Kubota Corp Frp molding material composition
JPH11188724A (en) * 1997-12-26 1999-07-13 Daikyo Inc Resin molding material, resin molded article and resin molding method using the same
KR20010008243A (en) * 2000-11-17 2001-02-05 이종철 The method and its products of used polyuretane foam

Similar Documents

Publication Publication Date Title
CN101157778A (en) Polypropylene composite material and method for recycling waste printing circuit board
CN111592707A (en) Plastic product filled and modified by artificial granite waste residue and processing method thereof
CN102558803A (en) Automobile bumper material and preparation method thereof
CN112980052B (en) Modifier and application thereof, modified heavy calcium carbonate and preparation method and application thereof
CN101190981B (en) Special-purpose material for automobile bumper and reclaiming utilizing method for waste printed circuit card
CN109721843A (en) Short carbon fiber mixing reinforced polypropylene compound material of a kind of fascia roving glass fiber and preparation method thereof
KR101349164B1 (en) Polyamide/PET alloy resin composition
KR20030092576A (en) A thermosetting recyclic resin
CN105733231A (en) Calcium sulfate whisker-modified polycarbonate alloy material and preparation method thereof
Younesi-Kordkheili et al. Nanolignin, a coupling bio-agent for wood-plastic composites
KR20150074482A (en) Recycling thermoplastic material with excellent impact strength
KR100199590B1 (en) Compositions for rubber filler
KR101371876B1 (en) The inorganic-intensed recycling polypropylene complex materials with a whisker or glass bubble as a substitute for a talc
CN1939970B (en) PC/ABS disposable recovering composition and its use
US7829184B2 (en) Motor vehicle part made of plastics material comprising polypropylene filled with glass fibers
CN101108911A (en) Modified plastic rubber composite material and method of preparing the same
KR0153321B1 (en) Manufacturing method of recycled board utilized used-carpet and carpet scrap
CN1939971A (en) PC/ABS disposable recovering composition and its use
JPH06345953A (en) Lightweight reinforced resin composition
JP2001072796A (en) Modifier for recycling plastic and process for recycling plastic material
KR101887885B1 (en) Light-weight recycled resin composition using recycled resin and preparation method therof
CN1508177A (en) Polyolefin resin/recovered paper powder/inorganic mineral composite material and preparing method thereof
CN101704997A (en) Halogen-free buckling deformation resistant reinforced high-temperature nylon and preparation method thereof
CN117683333A (en) Biodegradable composite material and preparation method and application thereof
KR100816803B1 (en) A recycling method for plastic materials of used vehicle lamp systems

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E601 Decision to refuse application