A kind of graphene/uhmwpe composite fiber and its preparation method and application

Abstract

The invention discloses a graphene / UHMWPE composite fiber and a preparation method thereof. In the composite fiber, the content of graphene is 0.05-5 wt% of that of UHMWPE. The preparation method comprises: pre-dispersing graphene in a solvent to form a uniform graphene dispersion liquid, fully dissolving UHMWPE powder in a solvent in a heating condition, fully mixing the obtained solution with the obtained graphene dispersion liquid, spinning the fully-mixed UHMWPE / graphene mixed solution through a gel-spinning method, and performing solvent extraction and drawing to obtain the graphene / UHMWPE composite fiber. The prepared graphene / UHMWPE composite fiber is obviously improved in the mechanical strength. The tensile strength can reach 29 cN / dtex, and the tensile modulus can reach 1300 cN / dtex. Through changing the addition ratio of graphene and UHMWPE powder, the size of graphene and different dispersion processes, the mechanical property of the composite fiber can be regulated.

Description

technical field [0001] The invention relates to an ultra-high molecular weight polyethylene fiber added with graphene, which belongs to the field of polymer materials. Background technique [0002] As one of the three high-performance fibers in the world today, ultra-high molecular weight polyethylene (UHMWPE) fibers have excellent specific strength and specific modulus, and have great advantages in lightweight composite materials. Areas such as sea area defense equipment play a pivotal role. In the late 1970s, the Dutch DSM company first developed the UHMWPE gel spinning technology, which made revolutionary progress in the strength and modulus of UHMWPE, and applied for the first patent on the preparation of UHMWPE fibers by gel spinning. Later, the Honeywell Company of the United States and the Toyobo Company of Japan successively developed the preparation technology for the commercial production of high-performance UHMWPE fibers, and applied for a large number of patents...

AI Technical Summary

Problems solved by technology

The particle size of graphene is small, and the strong van der Waals force is formed between the sheets due to the conjugated structure, making the sheets easy to stack and difficult to disperse

The traditional melt-blending composite method adopts the direct feeding method of graphene powder. Since the graphene is wrapped by the molten high-viscosity polymer, it cannot fully diffuse in the system, so that the effective dispersion of graphene cannot be guaranteed, making the graphene Excellent performance has not been fully utilized

Graphene, which is also an inorganic substance, has poor compatibility with the polymer interface, which affects the interface bonding force between it and polymers, and the mechanical properties are not significantly improved.

Patent CN201210078324 and patent CN201510165000 use coupling agent to modify graphene to improve its dispersibility and compatibility, but the reduced graphene surface active groups are less, grafting is difficult, and the graphene powder that has been agglomerated is very difficult. It is difficult to carry out secondary dispersion, which greatly affects the material properties

In addition, the solid state in melt blending or the liquid-solid mixing method adopted in patent CN201210078324 and patent CN201510165000 cannot achieve molecular level contact mixing between graphene and UHMWPE molecular chains, which directly affects the uniform distribution of graphene in the system

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