JP-7857353-B2 - Sheath-core composite polyethylene fiber and method for manufacturing the same

JP7857353B2JP 7857353 B2JP7857353 B2JP 7857353B2JP-7857353-B2

Inventors

張英
喩峰
陳小林

Assignees

江蘇▲ジン▼邦新材料有限公司

Dates

Publication Date: 20260512
Application Date: 20240718
Priority Date: 20230726

Claims (8)

Sheath-core composite polyethylene fiber, A sheath-core composite polyethylene fiber comprising a fiber core layer and a fiber sheath layer, wherein the fiber sheath layer encloses the fiber core layer, the fiber sheath layer contains ultra-high molecular weight polyethylene A, the fiber core layer contains ultra-high molecular weight polyethylene B, a first additive and a second additive, the first additive contains nanocrystalline silicon carbide powder, the second additive contains graphene, and the second additive may or may not contain a coloring agent and an antioxidant.
The sheath-core composite polyethylene fiber according to claim 1, characterized in that the amounts of the first and second additives used are 0.1 to 60% and 0.1 to 30% of the total mass of ultra-high molecular weight polyethylene B, the first additive, and the second additive, respectively.
The sheath-core composite polyethylene fiber according to claim 2, characterized in that the amounts of graphene, coloring agent, and antioxidant used are 0-10%, 0-20%, and 0-2% of the total mass of ultra-high molecular weight polyethylene B, the first auxiliary agent, and the second auxiliary agent, respectively.
The sheath-core composite polyethylene fiber according to claim 1, characterized in that the weight-average molecular weights of the ultra-high molecular weight polyethylene A and ultra-high molecular weight polyethylene B are both 1 million to 4 million.
A method for producing a sheath-core composite polyethylene fiber according to any one of claims 1 to 4, comprising the following S1 to S5: S1: Nanocrystalline silicon carbide powder is added to solvent A, pre-treated by dispersion and stirring, and then sanded to produce the first auxiliary agent. S2: Add graphene to solvent B, and optionally add color sizing agent and antioxidant. After the addition is complete, pre-treatment of dispersion and stirring is performed, followed by sanding to produce the second auxiliary agent. S3: After uniformly mixing ultra-high molecular weight polyethylene B, the first auxiliary agent, and the second auxiliary agent in solvent C, the mixture is introduced into a twin-screw extruder, heated, and extruded to dissolve and prepare a fiber core spinning solution. S4: Ultra-high molecular weight polyethylene A is added to solvent D and mixed uniformly, then introduced into a twin-screw extruder and extruded to dissolve and prepare a fiber sheath layer spinning solution. S5: A manufacturing method characterized by obtaining a sheath-core composite polyethylene fiber, which is a finished product, by enclosing the fiber core layer spinning solution with the fiber sheath layer spinning solution and spinning it, followed by extraction, drying, and heat stretching.
The manufacturing method according to claim 5, characterized in that, in step S1, when sanding, the particle size is controlled to be between 10 and 300 μm and the aspect ratio to be within the range of 1 to 30.
In step S3, the heating temperature is 200 to 300°C. In step S4, the heating temperature is 200 to 300°C. The manufacturing method according to claim 5, characterized in that in step S5, the spinning temperature is 220 to 260°C.
The manufacturing method according to claim 5, characterized in that solvents A, B, C, and D are all white oils.

Description

This invention belongs to the field of polymer materials, and more specifically, relates to sheath-core composite polyethylene fibers and a method for producing the same. Ultra-high molecular weight polyethylene (ULPE) fibers are high-performance chemical fibers possessing ultra-high strength and ultra-high modulus of elasticity. Their products are widely used in military applications (body armor, bulletproof helmets, other personal protective equipment, tanks, ships, helicopters, and other armored protective gear) and industrial applications (marine ropes, farmed fish, sporting goods, radomes, etc.). Conventional ULPE fibers have long molecular chains and are highly entangled, resulting in a generally low cut resistance grade of only around 2 (when ULPE fibers are blended with glass fibers, steel wire, etc., the comfort of the blended fibers deteriorates). Furthermore, due to their non-polar molecular structure and high crystallinity, ULPE fibers are difficult to dye and have poor colorfastness. In prior art, research on ultra-high molecular weight polyethylene fibers has been conducted. For example, patent application CN109322006A discloses colored high-strength polyethylene fibers and their manufacturing methods. By filling the fibers with components such as surface-modified nanoboron fibers, the cut resistance of ultra-high molecular weight polyethylene fibers can be improved to some extent without compromising comfort. Furthermore, by using a technology that combines doping and sheath-core composite technology, dyeing can be facilitated and colorfastness can be improved to some extent. However, conventional sheath-core composite polyethylene fibers still suffer from problems such as powder shedding and color fading when applied to subsequent processes, and they tend to wear down equipment in subsequent processes. There are also limitations to the improvement in cut resistance. Therefore, new technological means are needed to solve the above technical problems. The objective of this invention is to provide a sheath-core composite polyethylene fiber and a method for producing the same, thereby solving the technical problems of the prior art described above, specifically the fact that sheath-core composite polyethylene fibers tend to shed powder and fade in color when applied to subsequent processes, causing wear on equipment in subsequent processes and limiting the improvement of cut resistance. To achieve the above objectives, the present invention employs the following technical means. A sheath-core composite polyethylene fiber comprising a fiber core layer and a fiber sheath layer, wherein the fiber sheath layer encloses the fiber core layer, the fiber sheath layer contains ultra-high molecular weight polyethylene A, the fiber core layer contains ultra-high molecular weight polyethylene B, a first additive and a second additive, the first additive contains mineral fibers, the second additive contains at least one of inorganic ultrafine powder and graphene, and the second additive may or may not contain a color sizing agent and an antioxidant. The amounts used of the first and second additives are 0.1 to 60% and 0.1 to 30% of the total mass of ultra-high molecular weight polyethylene B, the first additive and the second additive, respectively. Specifically, the amounts used of the inorganic ultrafine powder, graphene, color sizing agent and antioxidant are 0 to 20%, 0 to 10%, 0 to 20%, and 0 to 2% of the total mass of ultra-high molecular weight polyethylene B, the first additive and the second additive, respectively. The mineral fiber is one of glass fibers, ceramic fibers, and carbon fibers, or a combination thereof. The inorganic ultrafine powder is one of aluminum, titanium, silicon, boron, carbides, nitrides, and zirconium oxides, or a combination thereof, with an average radius of 0.1 to 300 μm. The weight-average molecular weight of both ultra-high molecular weight polyethylene A and ultra-high molecular weight polyethylene B is 1 to 4 million. The present invention further provides a method for producing the sheath-core composite polyethylene fiber. This production method includes the following steps. S1: Mineral fibers are added to solvent A, and after pretreatment involving dispersion and stirring, the first auxiliary agent is produced by sanding. Here, solvent A is white oil. S2: At least one of inorganic ultrafine powder and graphene is added to solvent B, and a color sizing agent and an antioxidant may or may not be added. After the addition is complete, the mixture is pretreated by dispersion and stirring, and then sanded to produce the second auxiliary agent. Here, solvent B is white oil. S3: Ultra-high molecular weight polyethylene B, the first auxiliary agent, and the second auxiliary agent are added to solvent C and mixed uniformly. The mixture is then introduced into a twin-screw extruder, heated, and extruded to dissolve and prepare a fiber core spinning solution. Here, the heating