Chemical fiber oil

Make up

Smoothing agent

(lubricant)

The main function of the smoothing agent is to reduce friction, improve the strength of the oil film, protect the fiber, and prevent the wear and rust of the fiber on the equipment. Smoothness is essentially the friction characteristics of the oil agent, which is commonly expressed by the static friction coefficient (μS) and dynamic friction coefficient (μd) between the wire and the wire (F/F), the wire and the metal (F/M) and the wire and the rubber (F/R) after oiling. It is usually determined by the Raeder test. The oil film strength was tested by MRS 10 four-ball friction and wear test machine. The oil film strength is high and the friction coefficient fluctuation is small.

The smoothing agent generally selects mineral oil, vegetable oil, fatty acid mono alcohol ester, polyol ester, fatty acid double ester, fatty acid polyol ester, fatty acid trimethylol propyl ester, fatty acid pentaerythritol ester, etc. Industrial white oil is widely used as a smoothing agent in chemical fiber oil. However, due to its poor heat resistance, volatile at high temperature, poor oil film strength, its use in high-speed spinning such as POY is limited. Synthetic ester is the main smoothing agent for one step process FDY, industrial filament and other oils, and its performance is superior to that of natural mineral oil. They have the advantages of low volatility, strong oxidation resistance, low freezing point, good viscosity and temperature, high compatibility and easy emulsification. The smoothing agent generally accounts for 40% to 60% in the filament oil formulation, and the proportion is higher in the finished oil. There are many smoothing agents in the oil, and the smoothness of the fiber is good, but it increases the difficulty of preparing the emulsion.

Mineral oil

Liquid alkanes: such as liquid paraffin is generally a mixture of moderate molecular weight alkanes and cycloalkanes. According to the difference in viscosity, it is divided into different grades. The viscosity of mineral oil increases with the increase of molecular weight and the thermal stability increases with the increase of molecular weight. Because mineral oil has the characteristics of low price, good smoothness at low temperature, good sizing, etc., it is widely used in all kinds of ordinary spinning oil, the amount ranges from 5-50%, and even more than 80% in winding oil. However, because of its poor heat resistance, volatile at high temperature, it can not play its due lubrication role, coupled with the poor strength of the oil film, the use of high temperature and high speed spinning process is limited.

Solid alkanes: such as solid paraffin also has many kinds, its molecular composition is mostly large molecules of alkanes. Because it is solid at room temperature, it is generally not used for chemical fiber oil agents, and is only used as an additive in high-strength industrial silk or cord oil agents in a small amount to improve the oil film strength of the oil agent.

esters

Esters can be divided into natural oils and synthetic esters.

A. Natural oil: It is composed of triglycerides of advanced fatty acids. This kind of smoothing agent can be listed as coconut oil, soybean oil, peanut oil, corn oil and lard, etc., with the decrease of viscosity, its degree of unsaturation increases, due to its low price, good smoothness, less smoke, high oil film strength, often combined with other smoothing agents for all kinds of chemical fiber oil agents other than POY oil, but because its molecules contain double bonds, oxidation stability is poor, easy to coking, As well as poor sizing, the dosage is generally controlled within 8%.

B, synthetic ester: generally by various alcohols and advanced fatty acids through condensation esterification, transesterification and other ways to prepare. Commonly used alcohols can be listed as octanol, dodecyl alcohol, octadecyl alcohol, ethylene glycol, polyethylene glycol, glycerol, trimethylol propane, pentaerythritol, sorbitol and other monols and polyols, and advanced fatty acids from the source of raw materials, generally choose below octadecyl (including octadecyl) monic acid and polyacid. According to the needs can be made into different uses of single ester, double ester and polyester.

polyether

Polyether usually refers to the polymerization of ethylene oxide (EO) and propylene oxide (PO) under different starting agents to obtain polymer compounds. Starting agent multi-purpose alcohols, such as primary alcohols, polyalcohols, etc. Due to different starting agents, different ratios of EO and PO, different polymerization methods and different molecular weights, a wide range of polyether compounds have been formed.

POY spinning process for the oil agent required these characteristics, is other than polyether smoothing agents can not be done, so the amount of polyether in POY chemical fiber oil agent up to 70%. From the perspective of molecular structure, polyether molecules are hydrophilic with alkyl group at one end and alcohol hydroxyl group at the other end. The oxygen atoms in the ether group are easy to form hydrogen bonds with water, so most polyethers are easily soluble in water. Although the ratio of PO can be increased to increase the lipophilicity and improve its smoothness, it is still limited. In oils with high smoothness requirements, such as FDY oils, polyether is often used in combination with Taisen ester to make up for its lack of smoothness.