Abstract: Elastic fibers are widely used in many fields due to their low modulus, high elongation and excellent elasticity. Currently, the main types of elastic fibers on the market include polyurethane, polyolefin and polyether ester elastic fibers. However, polyurethane fibers are mostly prepared by solution spinning, which involves the use of organic solvents that can cause serious environmental pollution. Although environmentally friendly non-isocyanate polyurethane has improved in terms of environmental protection, its production cost is relatively high. Polyether ester elastic fibers suffer from inadequate elastic recovery and elastic stability. Conventional polyolefin elastic fibers have problems of poor hygroscopicity and obvious stress relaxation, which severely limit their applications in scenarios requiring high elastic recovery and stability. Therefore, there is an urgent need to develop a new type of elastic fiber or yarn.
Currently, the main improvement strategies for polyolefin fibers primarily involve mechanical blending to enhance their toughness. However, these methods are constrained by the melt processing feasibility of the modified materials and their compatibility with the polyolefin matrix, making it challenging to address defects such as hygroscopicity and stress relaxation. Chemical modification methods are complex and costly, especially the application research of the polyolefin fiber in core-spun yarns is even more scarce, which restricts its further development and application. In this paper, the ethylene-propylene copolymer Vistamaxx (VM) was selected as the polyolefin matrix to prepare elastic fibers through the melt spinning process. The effect of spinning temperature on the mechanical properties of the fibers was investigated. By adjusting the spinning temperature, the breaking elongation, strength, and cyclic tensile properties of the fibers were observed to find out the most suitable spinning temperature for VM fiber preparation. Different types of outer fibers, including cotton, aramid, and ultra-high molecular weight polyethylene (UHMWPE), were selected to prepare core-spun yarns, and further analysis was conducted on the improvement in mechanical properties and other aspects of these yarns. The results showed that Vistamaxx 6202 exhibited more balanced rheological properties, and the prepared fibers had a smooth surface without obvious defects or cracks. Additionally, when the spinning temperature was 175 ℃, the polyolefin fibers demonstrated optimal breaking elongation and cyclic tensile properties. In addition, wrapping the fibers with UHMWPE, aramid, and cotton significantly enhanced the yarn strength and durability while maintaining fiber elasticity. The prepared polyolefin core-spun yarns were uniformly wrapped, with no exposure of the core yarn.
Polyolefin fibers prepared by melt spinning exhibit excellent properties, and their core-spun yarns possess practical value. These results show that polyolefin fibers have potential application prospects in meeting the requirements of fabric strength and elasticity, and provide important support for the development of polyolefin fiber materials.

Key words: polyolefin elastomer, melt spinning, polyolefin fibers, core-spun yarns, tensile properties

摘要： 为推动弹性材料市场的发展，选用丙烯-乙烯弹性体Vistamaxx作为原料，通过熔融纺丝法制备聚烯烃纤维，探索了纤维表面形貌变化及纺丝温度对力学性能的影响，同时对其外包不同纤维制备包芯纱，研究了外包纤维对包芯纱拉伸性能的影响。结果表明：Vistamaxx 6202表现出更为均衡的流变特性，所制备的纤维表面光滑，无明显缺陷或裂纹，且当纺丝温度为175 ℃时，其表现出最佳的断裂伸长率和循环拉伸性能；另外，外包超高分子量聚乙烯、芳纶和棉纤维能显著提升了纱线的强力和耐久性，同时也能保持纤维的弹性。研究结果对Vistamaxx材料在纤维和纱线中的后续开发具有重要的技术借鉴意义。

关键词: 聚烯烃弹性体, 熔融纺丝, 聚烯烃纤维, 包芯纱, 拉伸性能