What is polypropylene yarn? Raw material of polypropyle […]
What is polypropylene yarn? Raw material of polypropylene yarn; about the introduction of polypropylene yarn, let's start with its biggest point. The biggest advantage is its light texture. Its density is only 0.91g/cm3, which is the lightest variety among common chemical fibers. Therefore, polypropylene fiber of the same weight can obtain a higher coverage area than other fibers. Strength and elongation Polypropylene has high strength, large elongation, high initial modulus and excellent elasticity. Therefore, polypropylene fiber has good abrasion resistance; in addition, the wet strength of polypropylene fiber is basically equal to the dry strength, so it is an ideal material for making fishing nets and cables; it has light moisture absorption and dyeing properties and good warmth retention; almost no moisture absorption, but strong wicking ability. The effect of moisture absorption and perspiration is obvious; polypropylene fiber has very little moisture absorption, almost no moisture absorption, and the moisture regain rate under general atmospheric conditions is close to zero. In addition, polypropylene fiber has good electrical insulation, but it is easy to generate static electricity during processing. Due to the low thermal conductivity of polypropylene, good warmth retention; high strength Polypropylene stretch yarn is second only to nylon in strength, but the price is only 1/3 of nylon; the fabric has stable dimensions, good abrasion resistance and good chemical stability.
The chemical molecules of polypropylene yarn are also very different, which are composed of polypropylene fibers. Polypropylene has good heat resistance, and the products can be sterilized at a temperature above 100°C, and will not deform at 150°C under the condition of no external force. The embrittlement temperature is -35℃, and embrittlement will occur below -35℃, and the cold resistance is not as good as polyethylene. The reported value of the glass transition temperature of polypropylene is 18qC, 0qC, 5℃, etc. This is also because people use different samples, which contain different ratios of the crystalline phase to the amorphous phase, which makes the chain length of the amorphous part of the molecular chain different. Caused by. The melting temperature of polypropylene is about 40-50% higher than polyethylene, about 164-170℃, and the melting point of 100% isotactic polypropylene is 176℃. The chemical stability of polypropylene is very good. In addition to being corroded by concentrated sulfuric acid and concentrated nitric acid, it is relatively stable to other chemical reagents. However, low molecular weight aliphatic hydrocarbons, aromatic hydrocarbons, and chlorinated hydrocarbons can soften polypropylene. Swelling, and its chemical stability increases with the increase of crystallinity, so polypropylene is suitable for making various chemical pipelines and fittings, and has good anti-corrosion effects. It is because of so many good points that polypropylene yarn is playing more and more roles and the market is getting bigger and bigger.