What factors affect the strength of polypropylene high strength yarn?
The melting index of the raw material indicates the molecular weight of the raw material to a certain extent, and the amount of fiber increases under the same process conditions. When the molecular entanglement is large, the strength of the stretched fiber increases with the increase of molecular weight, and when the molecular weight is low, it is easy to produce slip between molecular chains, which is manifested in the decrease of fiber strength. In the process of polypropylene high strength yarn, several raw materials with different melt indices are used.
In the test spinning process, it was found that under the same process conditions, the melting index of raw materials was different, and the strength of the finished silk was different, and showed a certain regularity.
Under the same spinning temperature, the same drawing multiple and the same process parameters, the lower the melt index of polypropylene slice, the higher the strength of polypropylene high strength yarn.
The influence of the stretching factor
The tensile process of the primary fiber destroys the original structural form of the primary fiber and generates a new order structure. Under the action of tensile stress and thermal effect, the activity of macromolecular chain segments increases, and various structural units gather along the axial orientation of the fiber, rearrange and add new binding points, so that more molecular chains of the fiber are in a particularly good stress bearing state. The regularity of the three-dimensional structure (that is, crystallization) is produced, and the fiber density increases with the increase of the tensile multiple.
The strength of the fiber increases with the increase of the tensile ratio, and the tensile ratio contributes more to the strength of the fiber.
Jiangyin Jinmeng Textile Co., Ltd. specializes in production and management: polypropylene high strength yarn, high-strength polypropylene yarn, woven geotextile, mold bag cloth, geotextile; High strength polypropylene industrial filament, engineering fiber, woven high strength industrial filament geotextile, engineering short fiber, Golden League textile; Polypropylene high strength industrial silk.