贴肤用熔喷非织造材料柔韧化改性及应用研究进展

Research progress of flexible modification and applications of skin-fitting melt-blown nonwovens

熔喷非织造材料是一种由超细纤维直接组成的柔性多孔介质,具有纤维比表面积大、结构蓬松和屏蔽性好等特点,在医疗防护和个人卫生等贴肤领域中具有广泛应用。然而,由于部分熔喷非织造原料的固有脆性,导致熔喷非织造材料存在柔软舒适性差的问题。因此,提升熔喷非织造材料柔韧性,已经成为贴肤用纺织品领域的研究热点。本文整理熔喷聚合物原料共聚改性和共混改性研究进展,介绍了熔喷非织造生产工艺对材料柔韧性影响规律,阐述了熔喷非织造材料在柔性贴肤领域应用形式,为熔喷非织造材料柔韧性提升与贴肤性应用提供研究思路。

Melt-blown nonwovens, flexible porous media made up directly of superfine fibers, not only have a large fiber specific surface area, fluffy structure and good shielding properties, but also have a wide range of raw material sources, short production processes and many product variations, and are currently used in a wide range of skin-fitting applications such as medical protection, personal hygiene and intelligent temperature regulation. However, the polymer raw materials currently used in melt-blown nonwovens are mainly polymers such as polypropylene, polyethylene and polylactic acid, which contain multiple rigid molecular chain segments in their structure, resulting in brittle nonwovens that are not sufficiently tough. Therefore, how to improve the softness of melt-blown nonwovens so as to further develop their application in the field of skin-fitting products has become a major issue and research hotspot in the field of skin-fitting textiles.This paper reviews the research progress on copolymer modification and blending modification of melt-blown polymer raw materials, summaries the influence of melt-blown nonwoven production processes on the flexibility of the materials and describes the forms of applications of melt-blown nonwovens in the field of flexible skin-fitting, providing references and new ideas for the flexibility improvement and skin-fitting application and development of melt-blown nonwovens.The high melt flow index, narrow molecular weight distribution and low melt viscosity of the polymer raw materials used in the melt-blown process not only help the polymer melt to draw into fibers, but also improve the flexibility of the nonwoven materials by introducing other substances. A common method of improving the softness of polymers is therefore the copolymerization and blending of polymeric raw materials in the melt-blown process, and a great deal of work has been done by many researchers to improve the softness of polymers. Copolymer modification is to introduce the specific molecular chain segments into the main polymer macromolecule chain through a chemical reaction, so as to change the polymer molecular structure to improve the polymer molecular chain flexibility. In contrast, blending modification can be done by blending elastomers, small molecule oligomers or soft masterbatches to reduce the rigidity of the blends, which is a common physical modification method to improve the polymer flexibility, with the advantages of simple operation process and low production costs. In addition, the control of the forming process of melt-blown nonwovens can be easily regulated. The flexibility of the nonwoven material can be improved by making the resulting fibers finer in diameter, more porous and fluffier in structure by adjusting the process parameters such as the receiving distance, hot air pressure, hot air temperature and die head temperature. Therefore, the study of the influence of process parameters on the structure and properties of nonwovens can provide a reference for the further improvement of the softness and comfort of melt-blown nonwovens and the development of skin-fitting materials.This paper presents a review of methods to improve the flexibility of melt-blown nonwovens and their skin-fitting applications. Based on this, it is found that adding flexible molecular chains to the macromolecular chains of polymer raw materials or melt blending them with flexible materials, or adjusting the parameters of the melt-blown nonwoven process, can effectively improve the flexibility of nonwovens. At the same time, there are several issues that need to be improved:(i) different types of polymer raw materials require different methods(chemical or physical) to improve material flexibility, and it should be considered that the method has the characteristics of simple operation, low cost and industrial mass production;(ii) it is also necessary to increase the diversity of functional applications of materials in improving the flexibility of melt-blown nonwovens, which is also a future melt-blown nonwovens research hotspot.More and more scholars will pay attention to the research of melt-blown nonwovens for flexible skin-fitting application as the field of application of melt-blown nonwovens expands. This paper reviews the polymer modification methods, melt-blown nonwovens processes and applications of flexible skin-fitting nonwovens, with the aim of providing a reference for subsequent research on melt-blown nonwoven flexibility enhancement and its application in new skin-fitting products.