WO2012062053A1

WO2012062053A1 - Preparation method for ultrahigh molecular weight polyethylene fiber

Info

Publication number: WO2012062053A1
Application number: PCT/CN2011/070752
Authority: WO
Inventors: 陈成泗; 许史安
Original assignee: 宁波大成新材料股份有限公司
Priority date: 2010-11-08
Filing date: 2011-01-28
Publication date: 2012-05-18
Also published as: CN102002769A; CN102002769B; EP2639346A1; EP2639346A4

Abstract

A preparation method with low energy consumption and low cost for ultrahigh molecular weight polyethylene fiber with high strength and high extension is disclosed. The method includes two steps: firstly, producing polyethylene modified master batch; secondly, adding so produced polyethylene modified master batch to a selected ultrahigh molecular weight polyethylene resin and uniformly mixing them, then melt spinning produced ultrahigh molecular weight polyethylene. The produced ultrahigh molecular weight polyethylene fiber has fiber strength of 15-25 CN/dtex and breaking extension of 5-8%. The method has merits of short production flow, low energy consumption, environmental protection, low cost, and high standalone capacity. The product can be generally used for twist-knitting all kinds of ropes, braiding fishnet and weaving all kinds of industrial cloths and belts and so on, and it can effectively keep a high fiber strength while being used.

Description

Preparation method of ultrahigh molecular weight polyethylene fiber

Technical field

The invention relates to an ultra-high molecular weight polyethylene resin using a melt spinning technology, and an innovative production method for preparing high-strength, high-stretch ultra-high molecular weight polyethylene fibers with low energy consumption and low cost. Background technique

Ultra-high molecular weight polyethylene fiber, with high strength, low density, high modulus, strong impact toughness, light resistance, good corrosion resistance, etc., is known as the world's three high-tech fibers (carbon fiber, aramid fiber, super High-performance new materials, one of high-strength polyethylene fibers, are widely used in defense military equipment, aerospace, special composite materials, marine engineering ropes and fishing nets. The production methods are known in the following two categories:

The first category: Dutch patent NL7900990, US patent US430577, European patent EP0064167, Chinese patent ZL85107352, ZL97106768. 6, ZL03106030. 7 , CN1995496A,

CN101205633A, CN101205637A and the like disclosed in the patent documents, all of which adopt a solution gel spinning method using decahydronaphthalene, mineral oil, paraffin oil, pure white oil and kerosene as a solvent, and the production process is carried out in four steps:

1. First, the ultrahigh molecular weight polyethylene resin is diluted and swelled in a solvent at a weight ratio of 5% to 25%. The solvent ratio is 75% to 95% (weight ratio), the swelling temperature is 90 ° C to 110 ° C, and the swelling is performed. Time 1 ~ 2 hours;

2. The swollen ultra-high molecular weight polyethylene solution is input into a twin-screw melt-squeezing spinner, and is quenched by cold water to form a jelly-like raw silk winding drum for storage;

3. The jelly raw silk is transferred into solvent gasoline or diphenylbenzene, dichlorosilane, etc. as an extractant by a tractor, and is reversely driven and extracted at a certain speed to completely extract the solvent in the jelly yarn;

4. The extracted virgin fibers are further dried, pre-stretched, and super-stretched into high-strength, high-modulus fibers using a tractor. This type of technology has a fiber strength of >30CN/dtex and a modulus of more than 1000CN/dtex. The technology is currently highly industrialized at home and abroad, and the technology is mature. However, there are drawbacks such as long production process, high energy consumption, high material consumption and high manufacturing cost.

The second category: Chinese patent document CN101230501A describes a technique for preparing high-strength polyethylene fibers by blending ultra-high molecular weight polyethylene with low-density polyethylene. The molecular weight of the ultrahigh molecular weight polyethylene selected in the technology is 120-1.8 million. The low-density polyethylene has a molecular weight of 2.5 to 40,000, and is spun by a twin-screw melt extrusion at a mixing ratio of 10:1, which has a fiber strength of 15 to 30 g/D and a modulus of 400 to 1000 g/D. The elongation at break is 2.5% to 3.5%. The technology uses two kinds of raw materials to mix, and there is a great difference in molecular weight distribution, resulting in extremely low fiber elongation (2.5% to 3.5%), such as multiple twisting of production ropes, fish net knitting, industrial fabric weaving. Such fields will lead to strong damage and large defects (strong loss will reach 30% ~ 60%), and should not be applied in ropes, fish nets and other fields. Summary of the invention

Through long-term research and extensive experiments, the applicant has invented an ultrahigh molecular weight polyethylene fiber capable of eliminating the defects of the above products, and a method for preparing the fiber.

The invention selects ultra-high molecular weight polyethylene powdery resin with molecular weight of 150-2.5 million as raw material, and adds polyethylene modified masterbatch according to weight ratio of 6% to 10%, and is subjected to screw melt extrusion spinning and super-stretching. Obtain high-strength, high-strength polyethylene fibers with a fiber strength of 15CN/dtex ~ 25CN/dtex and an elongation at break of 5% to 8%.

The specific preparation steps of the ultrahigh molecular weight polyethylene fiber of the present invention are as follows:

The first step is to prepare polyethylene modified masterbatch:

(1) Select LDPE low density polyethylene or LL0PE linear low density polyethylene as raw material, add P0E polyolefin elastomer, PE foaming agent, and EPDM or SEBS for uniform mixing;

(2) The polymer after homogenization is subjected to twin-screw blending and granulation to prepare a polyethylene modified masterbatch; the second step is to prepare ultrahigh molecular weight polyethylene melt spinning:

(1) using ultra-high molecular weight polyethylene resin, and adding the prepared polyethylene modified masterbatch uniformly; (2) conveying the mixture into a screw extrusion melt spinning, and then cooling the fiber through a water bath for winding forming;

(3) The wound fiber is further subjected to three times of super-stretching, and after drying and setting, a finished fiber is obtained.

The ultrahigh molecular weight polyethylene fiber of the invention is most suitable for all kinds of rope twisting weaving, fish net knitting, industrial cloth, industrial belt weaving, and does not cause strong loss. The method of the invention has the advantages of short production process, low energy consumption, environmental protection, low manufacturing cost and high single machine capacity, and is an innovative technology for sustainable development of high-strength polyethylene industry, and the invention realizes breakthrough of high-strength fiber and high-extension technology. The products can be widely used in various types of rope twisting weaving, fish net knitting and various industrial fabrics, industrial belts and other weaving fields, and can effectively use fiber strength during use. detailed description

The invention selects ultra-high molecular weight polyethylene powdery resin with a molecular weight of 150-2.5 million as a raw material, and according to the molecular weight of the raw material of the polyethylene resin, the polyethylene modified masterbatch is mixed with the weight ratio of 6% to 10%, Among them, 1 500,000 molecular weight polyethylene resin plus 6% polyethylene modified masterbatch, on this cornerstone, polyethylene tree The molecular weight of the fat and the amount of the polyethylene modified masterbatch increased by (100,000) / (0.4%), that is: for every 100,000 increase in the molecular weight of the polyethylene resin, the addition amount of the polyethylene modified masterbatch is increased by 0.4. %, until the molecular weight of the polyethylene resin is increased to 2.5 million, and the amount of the polyethylene modified masterbatch is increased to 10%, such as: 1.8 million molecular weight polyethylene resin plus 7.2% polyethylene modified masterbatch, 2.5 million molecular weight polyethylene resin Add 10% polyethylene modified masterbatch, etc.; then, through the length to diameter ratio 1:40 screw melt extrusion spinning and ultra-stretching, obtain high strength, high elongation polyethylene fiber, obtained polyethylene fiber The elongation at break is 5% to 8%, and the fiber strength is 15CN/dtex to 25CN/dtex. Among them, the fiber strength corresponds to the molecular weight value of the ultrahigh molecular weight polyethylene resin, namely: the strength of 1.5 million molecular weight polyethylene fiber 15CN/dtex, on this basis, the molecular weight of polyethylene fiber and its strength value increase by (100,000) I ( lCN / dtex), that is: for every 100,000 increase in the molecular weight of polyethylene fiber, the fiber strength increases by 1 CN/dtex, up to polyethylene 2,500,000 dimensional molecular weight increased, the fiber strength increases 25 CN / dtex.

First step Preparation of polyethylene modified masterbatch:

(1) LDPE low density polyethylene or LL0PE linear low density polyethylene is used as raw material, adding P0E polyolefin elastomer according to the weight ratio of 7%~15%, adding PE foaming agent according to the weight ratio of 3% ~ 5%, by weight More than 5% ~ 10% plus EPDM EPDM or SEBS for uniform mixing;

(2) The polymer after homogenization is granulated by twin-screw blending, the temperature of each section of the twin-screw is between 150 ~ 220 °C, and the speed of the twin-screw is controlled at 200 ~ 250 rpm, preparing for polymerization. Ethylene modified masterbatch.

The prepared polyethylene modified masterbatch has excellent functions such as low melting point, low viscosity, good lubricity, good fluidity, and easy dispersion.

The second step is the preparation of ultrahigh molecular weight polyethylene melt spinning:

(1) selecting an ultrahigh molecular weight polyethylene resin having a molecular weight of 150 to 2.5 million, and mixing the polyethylene modified masterbatch prepared in the first step by weight ratio of 6% to 10%;

(2) The mixture is conveyed into a screw extrusion melt spinning, wherein the length to diameter ratio of the screw is 1:40, the temperature of each section of the screw is 150 ° C ~ 250 ° C, and the screw extrusion speed is 200 ~ 250 rpm / Points, spinneret 100 ~ 150 holes, hole diameter 0.5 ~ 0.8mm, spinning melt temperature is controlled at 220 ° C ~ 240 ° C, nozzle drafting 5 ~ 15 m / min; sprayed primary fiber cooled by water bath, water The bath temperature is controlled at 20 ° C ~ 25 ° C; water bath cooling fiber for winding forming;

(3) The wound fiber is subjected to three times of super-stretching and one drying and finalizing, and finally the finished fiber is obtained, wherein the first ultra-stretching water bath is stretched, and the water bath temperature is 80 ° C ~ 95 ° C, the draw ratio is 5 to 10 times; the second ultra-stretching is carried out by superheated steam, the steam temperature is 110 ° C ~ 130 ° C, the draw ratio is 3 to 6 times; the third pass is dry heat Stretching, super stretching temperature is 120 ° C ~ 130 ° C, stretching ratio is 1.1 ~ 1.2 times; drying setting temperature is 130 ° C ~ 145 ° C, setting line speed per minute ~ 40 meters; Finally, made of ultra-high molecular weight polyethylene finished fiber;

The polyethylene fiber produced has a fiber strength of 15CN/dtex ~ 25CN/dtex and an elongation at break of 5%.

Claims

Rights request

1. An ultrahigh molecular weight polyethylene fiber, which is prepared by using an ultrahigh molecular weight polyethylene powdery resin having a molecular weight of 150 to 2.5 million, and adding a polyethylene modified masterbatch according to a weight ratio of 6% to 10%. It is obtained by melt extrusion spinning and ultra-stretching. The fiber strength is 15CN/dtex~25CN/dtex, and the elongation at break is 5%~8%.

2. A method of processing the ultrahigh molecular weight polyethylene fiber of claim 1 wherein the method is:

The first step is to prepare polyethylene modified masterbatch:

(3) The wound fiber is subjected to three times of super-stretching, and after drying and setting, the finished fiber is obtained.

3. The method of claim 2, wherein

In the first step (1), the P0E polyolefin elastomer is added in an amount of 7% to 15% by weight, and the PE foaming agent is added in an amount of 3% to 5%. The amount of EPDM or SEBS added is 5%~10%;

In the first step (2), the temperature of each section of the twin screw is between 150 ° C and 220 ° C, and the twin screw speed is controlled to be 200 to 250 rpm;

In the second step (1), an ultrahigh molecular weight polyethylene resin having a molecular weight of 150 to 2.5 million is selected, and the polyethylene modified masterbatch is added in a weight ratio of 6% to 10% according to the molecular weight of the polyethylene resin. Uniform mixing, in which 1.5 million molecular weight polyethylene resin plus 6% polyethylene modified masterbatch, on this basis stone, the molecular weight of polyethylene resin and the amount of polyethylene modified masterbatch added (100,000) I (0.4 The proportion of %) is increased, that is: for every 100,000 increase in the molecular weight of the polyethylene resin, the addition amount of the polyethylene modified masterbatch is increased by 0.4% until the molecular weight of the polyethylene resin is increased to 2.5 million, and the amount of the polyethylene modified masterbatch is increased. Increase to 10%;

In the second step (2), the length to diameter ratio of the screw is 1:40, the temperature of each section of the screw is 150 ° C ~ 250 ° C, the screw extrusion speed is 200 ~ 250 rpm, the spinneret 100 ~ 150 holes, hole diameter 0.5 ~ 0.8mm, the melt temperature of the spinning wire is controlled at 220 °C ~ 240 °C, the nozzle draft is 5 ~ 15m / min; the initial fiber sprayed is cooled by water bath, the temperature of the water bath is controlled at 20 °C ~ 25 °C; water bath cooling fiber for winding forming; In the second step (3), the three super-stretching, wherein the first super-stretching is stretched in a water bath, the water bath temperature is 80 ° C ~ 95 ° C, and the stretching ratio is 5 ~ 10 times; the second ultra-stretching is stretched with superheated steam, the steam temperature is 110 ° C ~ 130 ° C, the draw ratio is 3 ~ 6 times; the third dry heat drawing, dry heat temperature is 120 ° C ~ 130 ° C, the draw ratio is 1.1 ~ 1.2 times; the drying and setting, the setting temperature is 130 ° C - 145 ° C, the setting line speed is 20 ~ 40 meters per minute; Finally, the finished ultra-high molecular weight polyethylene The fiber and fiber have an elongation at break of 5% to 8%, and the fiber strength is 15CN/dtex to 25CN/dtex, wherein the fiber strength corresponds to the molecular weight value of the ultrahigh molecular weight polyethylene resin, namely: 1.5 million molecular weight polyethylene The strength of the fiber is 15CN/dtex. On this basis, the molecular weight of the polyethylene fiber and its strength value increase by (100,000) / ( lCN / dtex ), and the molecular weight of the polyethylene fiber increases by 100,000. CN/dtex, until the molecular weight of the polyethylene fiber is increased to 2.5 million, and the fiber strength is increased to 25 CN/dtex.