CN-122011550-A - High puncture resistance and wear resistance polyolefin film and preparation method thereof

Abstract

The invention relates to the field of polymer material processing, and provides a high puncture-resistant and wear-resistant polyolefin film and a preparation method thereof, through an innovative process combining 'wet bidirectional synchronous stretching' and 'gradient surface densification', the ultra-high molecular weight polyethylene porous membrane with compact and wear-resistant surface layer and porous high-strength gradient structure of the core layer is successfully prepared, and the material has excellent mechanical property and excellent surface tribological property while realizing ultra-thin and light weight. The invention is suitable for the fields of consumer electronics protection, sports equipment, medical equipment and the like.

Inventors

• FENG YUCHEN
• WU YUQIONG
• Song Die

Assignees

• 广东固纳科技有限公司

Dates

Publication Date

20260512

Application Date

20260213

Claims (10)

1. 1. The high puncture-resistant wear-resistant polyolefin film is characterized by comprising, by weight, 100 parts of thermoplastic resin, 55-65 parts of plasticizer and 0.3-0.6 part of antioxidant, wherein the thermoplastic resin comprises one or more of ultrahigh molecular weight polyethylene, high density polyethylene, linear low density polyethylene and polypropylene, and the molecular weight of the ultrahigh molecular weight polyethylene is 3.0X10 6 ~ 1.1×10 7 g/mol.
2. 2. The high puncture and abrasion resistant polyolefin film according to claim 1, wherein the plasticizer comprises one or more of liquid paraffin, dioctyl phthalate, paste paraffin, polyethylene wax, stearate.
3. 3. The high puncture and abrasion resistant polyolefin film according to claim 1, wherein the antioxidant comprises one or more of antioxidant 1076, antioxidant 168, antioxidant B900, antioxidant PEPQ, antioxidant KY-245.
4. 4. A method for preparing the high puncture-resistant and abrasion-resistant polyolefin film according to any one of claims 1 to 3, comprising the following steps: S1, premixing raw materials, namely weighing and mixing dry thermoplastic resin, plasticizer and antioxidant according to a formula proportion, and ensuring that all components are primarily and uniformly mixed to obtain a premix; s2, forming a precursor sheet, namely melting and blending premix, casting the premix onto a cooling roller through a T-shaped die, and forming a uniform precursor sheet; s3, biaxially stretching orientation, namely preheating a precursor sheet and biaxially stretching the precursor sheet; s4, heat setting, namely performing heat setting treatment on the stretched film; s5, extracting and pore-forming, namely immersing the film after heat setting into an extracting solution, and performing ultrasonic extraction to form a film with a porous structure; S6, drying, namely putting the extracted film into an oven for drying to obtain a pure porous film; And S7, surface densification, namely performing hot rolling surface densification on the porous membrane to obtain the high puncture-resistant wear-resistant polyolefin film.
5. 5. The method for producing a polyolefin film having high puncture resistance and abrasion resistance according to claim 4, wherein in the step S2, the precursor sheet thickness is 3 to 4mm, the melt blending temperature is 180 to 240 ℃, and the screw rotation speed is 200 to 400 rpm.
6. 6. The method for producing a polyolefin film having high puncture resistance and abrasion resistance according to claim 4, wherein in the step S3, the preheating temperature is 80 to 110 ℃, the stretching temperature is 130 to 140 ℃, the longitudinal stretching ratio is 4 to 16 times, and the transverse stretching ratio is 4 to 16 times.
7. 7. The method for producing a polyolefin film having high puncture resistance and abrasion resistance according to claim 4, wherein in the step S1, the heat setting treatment is performed at a temperature of 100 to 130 ℃.
8. 8. The method for preparing a polyolefin film with high puncture resistance and abrasion resistance according to claim 4, wherein in the step S5, the extraction liquid used in the extraction is a volatile solvent, the extraction temperature is 40-50 ℃, and the extraction time is 20-40min.
9. 9. The method for producing a polyolefin film having high puncture resistance and abrasion resistance according to claim 4, wherein in the step S2, the drying temperature is 50 to 60 ℃.
10. 10. The method for producing a polyolefin film having high puncture resistance and abrasion resistance according to claim 4, wherein in the step S7, the roller temperature for the surface densification treatment by hot rolling is 135 to 145 ℃ and the line pressure is 5 to 15kN/cm.

Description

High puncture resistance and wear resistance polyolefin film and preparation method thereof Technical Field The invention relates to the field of polymer material processing, in particular to a high puncture resistance and wear resistance polyolefin film and a preparation method thereof. Background Ultra-high molecular weight polyethylene (UHMWPE) has excellent wear resistance, high impact strength and low friction coefficient due to its extremely high molecular weight, and is widely used in the fields of artificial joints, safety protection, industrial wear-resistant parts, and the like. However, in practical applications, conventional UHMWPE materials and their modified articles face two prominent technical contradictions: First, there is a contradiction between weight reduction and high mechanical properties of materials. UHMWPE products produced by conventional processes (e.g. compression molding, pressure casting) have relatively low internal crystallinity and random molecular chain orientation, resulting in limited intrinsic mechanical strength. In order to meet the strength and wear resistance required by use, the thickness of the product is often required to be increased or a large amount of inorganic filler is added, but the thickness and flexibility of the product are directly reduced, and the requirements of modern industry on thinning and light weight are difficult to adapt. As in the prior art, CN114634663a patent discloses an abrasion resistant composite of Ultra High Molecular Weight Polyethylene (UHMWPE) and zirconium tungstate. The technical scheme is that the method adopts the traditional mould pressing technology, namely UHMWPE powder and zirconium tungstate particles are subjected to physical blending, then the mixture is put into a mould, hot press forming is carried out by adopting a gradient boosting method at 160-185 ℃, and finally cooling and demoulding are carried out, so that the product is obtained. The technology improves the wear resistance by adding external hard particles (zirconium tungstate), but the strengthening mechanism has limitation, the performance improvement is completely dependent on the addition of the external hard particles, the process does not change the unordered and unoriented original state of UHMWPE molecular chains, and therefore, the upper limit exists for the improvement of the intrinsic strength of the material. In order to pursue higher indexes, the traditional thinking is only to increase the proportion of filler or increase the thickness of the product, which directly conflicts with the "thinning" and "lightening" targets pursued by the modern industry. The essential core of the process is static die hot pressing, and high-rate directional stretching cannot be performed on the material, so that a highly oriented fibrous crystal network cannot be built in, and the performances of puncture resistance, tear resistance and the like of the material, which depend on a toughness network, are difficult to break through. Secondly, the contradiction that the surface tribology performance and the body mechanical performance are difficult to cooperatively improve is caused. The prior art generally employs physical blending of functional fillers to improve surface lubricity. However, this "bulk blending" modification is only focused on the surface properties and does not alter the disordered, weakly oriented microstructure within the UHMWPE matrix, and thus fails to simultaneously enhance the intrinsic toughness, impact and puncture resistance properties of the material. In addition, when the performance is improved by gamma-ray crosslinking and other modes, the material is easy to oxidize and degrade, and the long-term stability is influenced. For example, CN117209875A discloses a solution for improving the surface properties of UHMWPE by introducing functional fillers. The technical core is that firstly, manganese phosphate trihydrate nano-sheets with lubricating potential are prepared, and the nano-sheet powder and ultra-high molecular weight polyethylene (UHMWPE) resin powder are mechanically blended so as to be uniformly mixed on a macroscopic scale. And then the mixed powder is put into a mould, and the mixture is heated at 160-180 ℃ by adopting a hot press molding method to melt UHMWPE, and simultaneously pressure (finally 120-150 MPa) is applied to mold and solidify the material. In the friction process, the added manganese phosphate nano-sheet is designed to form a layer of lubricating protective film on the surface of the material, so that the friction coefficient and the abrasion loss are reduced. But this patent is optimized for lubrication only for the "surface" of the material in contact with the outside world. The whole process does not change the microstructure of the UHMWPE matrix at all, and does not make any active enhancement design on the arrangement, orientation and crystal morphology of polymer molecular chains. Since the structure of the