Abstract This paper analyzes the market and production technology of micropowder wax and the technical indicators of domestic and foreign manufacturers. And provide useful solutions to some of the problems in the application.
Keywords: micro wax printing ink
First, the market overview of micropowder wax
Ultrafine powder technology is a high technology developed in recent years. Generally, particles with a particle size of less than 0.5 μm are called ultrafine particles, particles with a size of 20 μm or less are called fine particles, and aggregates of ultrafine particles are called ultrafine particles. . Micronized waxes are widely used in printing inks, paints, and coatings for their excellent properties, improving scratch resistance, abrasion resistance, increased slip, resistance to sticking, disbonding, and improving handfeel; improving anti-adhesion , Anti-fouling performance, can control the gloss of printing inks, prevent the pigment from settling, produce high-performance matte inks and paints with matte powder, etc., and has become an indispensable important additive in the production of paints and inks.
Micropowder is an ultrafine powder with a particle size range of 2 to 30 μm and a broad molecular weight distribution, ranging from 600 to 6000, and is widely used. Most of the fine powder waxes are produced by various micronization processes from polyethylene wax, Fischer-Tropsch wax, polypropylene wax, polytetrafluoroethylene, and modified waxes thereof. Another part is amide wax, microcrystalline wax, natural wax produced by micronization process.
(1) Polyethylene wax: It is made by direct polymerization of ethylene monomer or by cracking of polyethylene.
About 1000-5000, the melting point is 100-120°C. It has excellent anti-friction, anti-scratch, anti-adhesion and gloss retention. It has a wide range of application. Branch structure, wear resistance is better. There are differences in the properties of high-density and low-density polyethylene micropowders.
(2) Fischer-Tropsch wax: It is produced from coal gas and is polymerized into a non-branched linear wax by the Ficher-Tropsch process. Its molecular weight is about 500 to 1,000. Low melting point, excellent smoothness and improved hand feel. Wax is smooth, feels strong, and easily disperses.
(3) Polypropylene wax: Compared with polyethylene wax, it has higher softening point and hardness, outstanding anti-blocking performance, prominent wear resistance, and improved metal scratch resistance, preventing pigments and silica from being used in inks and coatings. The settlement in the medium, but the compatibility is somewhat poor, difficult to disperse.
(4) Polytetrafluoroethylene wax: higher softening point, higher density, excellent heat resistance, outstanding slip, abrasion resistance, scratch resistance, and anti-adhesion. Hydrophobic and antifouling, excellent overall performance, difficult to disperse, high price.
(5) Modified micro-powder wax: modification of polyethylene wax or synthetic wax with polytetrafluoroethylene to increase the softening point and hardness of polyethylene wax, and increase the smoothness, wear resistance, scratch resistance and anti-blocking property. Improve the disadvantages of difficult dispersion of polytetrafluoroethylene wax and high price.
The preparation of ultrafine powder wax from high-molecular wax has three main ways: First, starting from coarse particles, mechanical comminution method, evaporation and precipitation method and melt spray method and other physical methods; second, the use of chemical reagents to make the formation of The various dispersed state molecules gradually grow into particles of desired particle size, which can be divided into two methods of dissolving and emulsifying; the third is directly regulating polymerization or degradation. Such as PMMA powder, controlled molecular weight PP, dispersion polymerization to prepare PS micro-powder, thermal cracking, radiation cracking PTFE powder. In China, manufacturers mainly use physical methods to prepare various micropowder waxes.
Domestic research and production of micro-powder wax started late, but the demand has increased year by year. The relatively large-scale production includes the Fine Chemical Plant of Beijing University of Chemical Technology and the Institute of Materials of Qiqihar University. The application of polyethylene micropowder abroad is very wide, and the demand is large. Only Japan produces about 3,000 tons per year, and the price is about twice as high as that of ordinary resins. Due to the low output of micropowder in our country, we can only meet part of the market demand. The other part of the market demand mainly depends on the import of polyethylene and micro wax products from Germany and the United States, such as: U.S. Allies, Sanye, Degussa of Germany, Hoechst, BASF, Clariant, and Sanyo Chemicals Co., Ltd. of Japan. Japan's petrochemicals, Japan's Mitsubishi Chemicals, Taiwan's Deqian, but generally higher prices, the market price of micronized polyethylene wax are generally around 23,000 to 35,000 yuan / ton.
Second, the technical indicators of various manufacturers
Although there are many wax production methods, micronized waxes are still the most, and there are many types of micronized wax on the market, and the manufacturing processes of all manufacturers are also different, making the particle size distribution of the micronized waxes in each plant relatively. The molecular mass, density, melting point, hardness and other properties are somewhat different.
1. The technical specifications of polyethylene micropowder in the fine chemical plant of Beijing University of Chemical Technology are as follows:
2. The technical specifications of polyethylene micro wax in the Institute of Materials, Qiqihar University are as follows:
3, Germany Clariant company powder wax technical indicators
4. Clover Company's Micro Wax Technology Index
5, Degussa's micro wax main technical indicators are as follows