The main factors that determine the strength and elongation of polypropylene staple fiber yarn are the fiber properties and yarn structure. Blended yarns are also affected by the differences in the properties of blended fibers and the blend ratio.

1, the nature of the fiber

Length of fiber, linear density:

Longer fiber length, thinner fibers, the larger friction between the fibers in the yarn resistance, easy to slip, so the yarn strength is higher.

When the fiber length uniformity is good, the fiber fine and uniform, into a uniform yarn, weak ring less significant, is conducive to the improvement of yarn strength.

Fiber strength:

When fiber strength and elongation are large, the strength and elongation of the yarn become larger. The fiber strength and elongation uniformity are small, then the yarn strength is high.

Fiber surface friction properties:

When the friction coefficient μ of the fiber surface increases, the sliding resistance between the fibers is large, the length of the slippage lc decreases, the proportion of the number of slippage fibers decreases, and the yarn strength increases. Increasing the number of crimp fibers can increase the sliding resistance between fibers.

2, yarn structure

(1) The influence of polypropylene staple fiber yarn structure on its strength and elongation is mainly reflected in the twist.

When the twist increases, the frictional resistance between the fibers increases, which is not easy to slip, which is conducive to increasing the strength of the polypropylene staple fiber, but with an increase in twist, with the increasing pitch of polypropylene staple fibers, polypropylene staple fiber strength The effective axial force of the yarn is reduced, the fracture of the yarn in the fiber is not synchronous, and the increase of the diameter of the yarn when the fiber is inclined is the unfavorable factor to the relative strength of the yarn.

(2) the impact of the joint stock

The combination of single yarns makes the plyyarn strips to be even, and there is contact between the single yarns so that the cohesion between the outer yarns of the single yarns increases. The strength of the yarns is greater than the sum of the strengths of the yarns.

(3) The arrangement of polypropylene staple fibers in spun yarn

Rotor yarn strength is lower than the ring yarn: rotor yarn, fold, curl, circular irregular arrangement of more fibers, less normal transfer of fibers, resulting in poor fiber-fiber co-intubation, stretching more slippage fibers .

Hai'an Qinfeng Chemical Fiber Co., Ltd. specializes in the production and sale of various staple fibers, including polypropylene staple fiber, polyester staple fiber, functional polypropylene staple fiber, functional polyester staple fiber, hydrophilic polyester staple fiber,PP staple fiber, Polyester staple fiber and so on.