Impact modifiers suppliers

In the past, impact modifiers often came with side effects, such as a reduction in tensile strength, modulus, heat distortion temperature, weathering performance, and clarity. It has been the objective of impact modifier suppliers to offer improved impact strength, even at low temperatures, without these or other disadvantages. Advances in blending and compatibilising technology now enable suppliers to use rather more complex formulations. 

A large number of grades is available, one supplier alone offering about 40, including unreinforced, glass- and carbon-fibre reinforced, mineral filler reinforced, impact modified, elastomer modified, flame retardant and various combinations of the foregoing. 

The level of technical service support provided for a given product generally tracks in large part where the supplier considers their product to be located within the spectmm of commodity to specialty chemicals. Technical service support levels for pure chemicals usually provided in large quantities for specific synthetic or processing needs, eg, ammonia (qv), sulfuric acid (see SULFURIC ACID AND SULFUR TRIOXIDE), formaldehyde (qv), oxygen (qv), and so forth, are considerably less than for more complex materials or blends of materials provided for multistep downstream processes. Examples of the latter are many polymers, colorants, flocculants, impact modifiers, associative thickeners, etc. For the former materials, providing specifications of purity and physical properties often comprises the full extent of technical service required or expected by customers. These materials are termed undifferentiated chemicals (9),... 

What are the costs and risks of processing impact-modified compounds Unlike in some PO resin situations, major suppliers of impact-modified POs capitalize on years of experience, economies of scales and their large equipment investments to produce reasonably priced high-impact compounds. Since impact modification is often not a straightforward process, using a specialty supplier may ultimately minimize costs for processors with limited access to specialized compounding equipment or expertise. 

The mechanical properties are often virtually unchanged by additives, although a few (fillers, impact modifiers) are expressly designed to have that effect. In some cases it can be difficult to tell the difference visually between the base polymer before and after addition of the additives, unless of course they include a pigment. Nevertheless trace substances can have tremendous effects on the ultimate durability and the selection of the correct grade or mixture for an application is essential. The advice of the materials suppliers must be considered when selecting a resin for durability. 

Many plastics do not have sufficient impact resistance for the use for which they are intended. Rather than changing to a different type of plastic, they can be impact modified in order to fulfill the performance in use requirements. Addition of modifiers called impact modifiers or tougheners can significantly improve impact resistance. These are one of the most important additives. There are many suppliers and chemical types of these modifiers. 

Commercial impact-modified PPs based on such blends exhibit excellent notched Izod impact strengths ranging from 80 to 800 J/m and moduli ranging from 1,000 to 1,700 MPa. Because of the large number of commercial suppliers and grades, no attempt will be made to describe the properties of any specific types of commercial impact-modified PP blends, except to generalize the trends in the impact/modulus behavior with respect to the content and the nature of the EPR. 

There are over 30 suppliers of impact modifiers worldwide. Most concentrate their efforts in one type of modifier as a result of their developed technologies and backward integration. Selected suppliers resell other producers technologies in their home regions to broaden their product lines... 

Rohm and Haas, Kaneka, and Atochem are the leading suppliers of impact modifiers worldwide. Each has strong positions in both the acrylic and MBS-related modifiers. Elf Atochem is stronger in acrylics, while Kaneka is stronger in MBS types. Rohm and Haas, including its joint venture with Kureha in the Asia/Pacific region, has a more balanced position. Table 4.16 presents the major global suppliers of impact modifiers by type. 

Many other chemicals have become more expensive because of increases in the price of upstream intermediates. Tin stabilisers are affected by the rising price of tin metal and epoxy derivatives are also affected, with basic epoxy resins going up by about 200 euros/tonne in Eiuope in mid-2004. Some phenohc derivatives have also risen dramatically in price. A snapshot over two or three months diuing mid-2004 shows substantial price increases being announced by leading suppliers for impact modifiers, waxes, silica, phosphorus flame retardants and, as indicated earlier, brominated types. Plasticiser producers were also attempting price increases for DINP and DEHP. 

Several manufacturers of heat stabilisers, impact modifiers and process aids were raided early in 2003 by competition officials in Europe, Japan, Canada and the USA. The Japanese companies included Kaneka, Kureha Chemical and Mitsubishi Rayon. Fourteen European PVC additive suppliers were said to be involved, including Akcros Chemicals, Arkema, and Rohm and Haas, as well as suppliers in the Netherlands, Italy, Germany and Belgium. 

Block copolymers containing 20-40% styrene are also useful as impact modifiers for ignition-resistant HIPS as well as other polystyrene resins. Kraton rubbers are available from Shell Chemical Co. and Vector rubbers are available from Dexco Polymers (a joint venture between The Dow Chemical Co. and The Exxon Chemical Co.). Both grades are used extensively for this purpose as are other similar products from other suppliers. Kraton rubbers are usually triblock copolymers of SBS type. The center block is polybutadiene with terminal blocks of polystyrene (49-51). By far the largest use of block copoljuners is in the form of TIPS resins. There are a number of suppliers, with Phillips Petroleum and BASF... 

Table 1 provides a list of suppliers of impact modifiers for engineering resins. 

The two main types of PP are homopolymer and copolymer, with homopolymer PP being the most widely used type. In general, it is stiffer and stronger than the copolymer type. Copolymer PP generally is softer than homopolymer, but is tougher and more durable, with better low-temperature toughness. Copolymer is usually divided into subgroups i.e., block copolymer, random copolymer, and impact-modified copolymer. All of these types of PP are readily available from a wide variety of suppliers and distributors. 

DuPont—Dow is the primary supplier of these polymers. There is an estimated 18,000 t of these elastomers used per year. The main uses of CPE are in construction, automotive, and electrical applications. These include power steering hose, electrical cords used in low voltage applications (extension cords, ignition wire), pond liners, and as a plastic modifier to improve impact modification. 

Software changes Assess software updates for compatibility with the existing software with particular emphasis on any changes made. In terms of system or standard software products, there is normally a bug fix list and details of new, modified, and removed features. Supplier s documentation should include an analysis of the impacts of the patch on their system, and this should be used by the customer to assess the extent of testing required to validate the patch implementation. These documents should be assessed to determine the effects of the change and any appropriate testing performed and incorporated into a validation dossier. 

Before accepting Heskett et al. s model as a basis to build upon, some other considerations are required. We have seen a number of important considerations take on increasing importance in the business environment. Healthcare is a business this is more obvious in some countries than it is in others—those without a social welfare system that includes a measure of state provided health services—and within which an important partner/ supplier is the health insurance provider. Both sectors are cognizant of the impact of their role on the socioeconomic fabric of the environment within which they operate. Accordingly we should modify Heskett et al. s model [17] to include this increasingly important consideration see the following socially responsible value equation ... 

EPDM and EPR are used to modify polyolefins, primarily in the automotive industry. The largest volume is in automotive PP bumpers. This application is gradually being replaced by impact-resistant polymers produced by metallocene technology, providing better performance and economics. DuPont Dow and Exxon are leading producers in North America. When used with plastics such as nylon, PET, and PBT, the EPDM and EPR are often modified with a functionalized monomer to allow them to react with the plastic. Additionally, the shell of a core-shell modifier can also be modified to include a reactive group. Suppliers of fimctionalized modifiers include Rohm Haas, AtoFina, Shell, and Exxon. 

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