PVC impact modifiers Excellent performance
With the rapid development of the global plastics industry, PVC Impact Modifier development is also advancing by leaps and bounds. In recent years, the average annual growth rate of plastic PVC industry reached 4% -6%, has exceeded the level of GDP growth. The main reason for this growth is that plastic materials continue to replace traditional materials such as metals, wood, and minerals. In fact, the various additives added to the resin for the successful application of plastic materials is also helpful. Among the various types of additives used, impact modifiers and PVC impact modifiers provide the most exclusive and valuable performance for polymers, while also improving the processability of the product. Toughening treatment, rheological performance control, appearance aesthetics, processing performance and economic factors are important properties of the property. All these additives have been used for many years, after a long period of development derived from a wide range of varieties. One of the main reasons for this is the diversity of the emulsion polymerization process, which allows scientists to continuously design suitable polymer components, polymer structures, polymer morphology and polymer molecular weight / molecular weight distribution. The emulsion polymerization is still very attractive in commercial production due to the low cost of production and the ease of separation of the resulting emulsion product.
In 1956, the first polymer additive for emulsion polymerization was developed, which is a core-shell structure Impact Modifier prepared from methacrylate-butadiene-styrene (MBS). Followed by a variety of acrylic processing aids and Acrylic Impact Modifiers. Initially, these additives are mainly used to improve the processing performance and toughness of polyvinyl chloride (PVC). The Processing Aid for PVC is mainly to promote the melting of PVC, enhance the melt strength, improve the dispersion performance and surface quality. Ultra-high molecular weight processing aids are an important part of foamed PVC. With the aid of processing aids, PVC foams can achieve a more uniform foam structure, reducing breakage of the closed bubbles and a lower foam density. Lubricating processing additives can effectively prevent the molten plastic bonding on the metal surface, improve the surface quality of products, improve production efficiency.
There are a lot of plastic materials that have a very limited range of applications because they do not have the required physical properties or are very poor in their processing properties. The processing aid is used to enhance the melt processability of the plastic, increase production and reduce parking Maintenance time and to provide better quality products. In the 1950s, Rohm and Haas took the lead in developing the first commercially available processing aids, which were used for rigid PVC production. After that, this unprecedented technology was soon known by the industry, and thus triggered the production boom of the PVC industry. Since the 1980s, such research and development work began to develop for other thermoplastic materials and polymer blends. Most of the processing aids are usually added to the PVC, while the processing aids used in other thermoplastics are few (only 0.5% to 5%), but nevertheless, these processing aids are significantly Improve processing performance, while not on other application performance caused too much impact. Depending on the functionality, the processing aid can be divided into flux, melt rheology modifier, lubricant and dispersion accelerator. In fact, each type of processing aids have more than one effect. The functionality and application of any of the processing auxiliaries depends on their chemical composition, polymer structure, polymer molecular weight, and the matrix type of the polymer.
