Polypropylene (PP Polypropylene) is a rising star in synthetic fiber, the scientific name of polypropylene fiber. Polypropylene yarn production process is simple, there are "one-step spinning" and "two-step spinning". The propylene is used as a raw material for polymerization, and the raw materials are modified, melt-spun, melted by melt filtration, blown, cooled, and wound to obtain fibers. Compared with the production process of “two-step spinning”, “one-step spinning” has the characteristics of less land occupation, less users and lower cost. The problem is that the strength of polypropylene yarn produced by “one-step spinning” process is low. Therefore, it is very important to modify its raw materials. At present, the production method of polypropylene filament is used. It is characterized by using polypropylene resin with melt flow index MFI=5-40 and molecular weight distribution index MWD<7, spinning at 400-1600/min. The quick-spinning wire is formed, and then subjected to two-stage drawing and twisting in a spindle-type traction twisting machine to obtain a high-strength polypropylene filament having a multifilament fineness of 400-1600 dtex.

The polypropylene filament is melted near the flame, is flammable, burns slowly from the fire and emits black smoke. The upper end of the flame is yellow, the lower end is blue, and the oil smell is emitted. After burning, the ash is hard round, light yellow and brown particles, and the handcuffs are brittle. Due to the simple production process, the products are cheap, high in strength and relatively light in density. It is now the fourth largest variety of synthetic fibers and the lightest of the most common chemical fibers. However, it has poor thermal stability, is not resistant to the sun, and is prone to aging and brittleness. For this reason, an anti-aging agent is often added to the polypropylene.

Uses: Can be used to weave a variety of knitwear such as hosiery, gloves, sweaters, knit pants, dish cloth, mosquito net cloth, wadding, warm filler, wet diapers, etc. Carpets, fishing nets, canvas, hoses, concrete reinforcements, etc.

Oversized Sunglasses

We mainly manufacture and export Sport Sunglasses, Fashion Sunglasses, unisex Sunglasses , Reading Glasses, optical frames and packing accessories since 1990s. We accept the OEM orders from all over the world. Just give us your idea and requirements, we will give you our most professional suggestions and services. For example, we recommend suitable styles for your reference if you`d like to buy sunglasses for man, sunglasses for woman, sunglasses for kids and your favorite colors and shapes. If you want to buy photochromic sunglasses, fishing sunglasses, biking sunglasses, hiking sunglasses, beach sunglasses, travelling sunglasses or sunglasses for outdoor activities, we can introduce the styles you like. If you have no idea about the sunglasses, we can bring the up-to-date styles or most classic styles to your attention.