776-00301 TYRIN IM bro - The Dow Chemical Company

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2 of 9 TYRIN 6000 CPE and TYRIN 7000 CPE Impact Modifiers TYRIN Chlorinated Polyethylene (CPE) thermoplastic resins are widely used as impact modifiers in PVC extrusion and injection molding applications. Especially effective in products such as window profiles, pipe, and siding, TYRIN 6000 CPE and TYRIN 7000 CPE provide excellent corner weld strength and high surface gloss. These resins offer high impact efficiency and perform well at low temperatures, giving very good weather resistance for all climate conditions. The resins can be blended with acrylics resulting in an optimum cost/performance solution. TYRIN 7000 is available in bulk, supplied by truck and can be stored in silos. TYRIN CPE offers the possibility to reduce the overall color pigment costs on colored window profile applications. Furthermore, TYRIN CPE resins work particularly well with calcium-zink stabilization to control gelation levels and melt temperature. All in, TYRIN resins help fabricators and compounders meet increasingly critical performance requirements and cost-control needs. Real Solutions Dow provides solutions that help meet the unique processing and performance requirements of current and next generation impact modification products, along with technical support that extends from formulation through processing and end-use requirements. The Global R&D Center in the USA, along with Dow’s local Technical Service & Development facilities, have the scientists, equipment, and technologies to provide a very high level of customer-focused services. ® Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow Product Properties The typical product properties of TYRIN 6000 and TYRIN 7000 are summarized in Table 1. They are both free flowing white powders, produced by the chlorination of low pressure polyethylene in a water slurry. Table 1: Typical properties of TYRIN CPE grades for impact modification Typical Properties Units Test Method TYRIN 6000 TYRIN 7000 Chlorine content Melt Viscosity wt % ISO 1158 35 35 (145 s-1 , 190°C) Pa.s ISO 11443 2400 2900 Heat of Fusion J/g EH-TYR-QP-AV 2011
PVC Modification Polyvinyl-chloride (PVC) is an outstanding material for the production of rigid extruded goods, such as pipes or profiles. However due to its high glass transition temperature, it has shortcomings in impact strength. It has therefore to be modified to provide impact strength at ambient and low temperature. Impact modifiers provide PVC compounds a consistently ductile behaviour over a broad temperature range. They are flexible materials which are partially compatible with PVC. They form a discrete phase in the PVC matrix, which absorbs and dissipates shock energy. During suspension polymerization of PVC grain particles with a typical diameter of 65-150 microns are formed. (Figure 1). These consist of smaller particles ranging from 0.2 to 1.5 microns in size: the primary particles. When the PVC powder is being processed into a fabricated product (e.g. by extrusion, calendering) the grain structure is broken down mainly by shear and the primary particles are molten together at their surfaces. The dominant factor in controlling the degree of fusion is the melt temperature and the additive package, consisting of stablizers, lubricants, fillers, and impact modifiers can affect the range of processing conditions required for optimum impact strength. This process is called fusion or gelation. The achieved impact strength is controlled by the degree of fusion of the PVC matrix. An under fused or over fused melt lowers the impact strength of the final product. Trademark of The Dow Chemical Company (“Dow”) or an affiliated company of Dow Essentially two classes of impact modifiers exist, which are physically blended with s-PVC during extrusion on twin screw extruders. Acrylic based modifiers are often used, which are core-shell particles of typically a butyl-acrylate flexible core with a rigid shell of poly-methyl-methacrylate. The shell enables a good flowability of the product and a good compatibility to PVC to enable a good dispersion. TYRIN Chlorinated Polyethylene (CPE) is a thermoplastic material and its morphology will develop during the melt processing of the PVC dry-blend. TYRIN CPE and other low melting ingredients will coat the PVC particles. Figure 1: Primary particles structure of s-PVC 65-150 Micron During subsequent extrusion a phase inversion occurs and creates discrete CPE particles in a continuous matrix of PVC. TYRIN CPE offers an excellent combination of compatibility, processibility, weatherability, and impact efficiency in many rigid PVC formulations, like window profiles, pipes, rigid and foamed sheet, etc. The use of TYRIN CPE makes it possible to use higher filler levels because being thermoplastic in nature, it flows and encapsulates inorganic filler particles. This coating provides a mechanism to control the particle adhesion to the PVC matrix and thus improves the contribution to impact resistance, whereas the filler aids TYRIN dispersion. Primary Particles Skin Grain 3 of 9
Page 1: Window Profile, Pipe, and Rigid She
Page 5 and 6: Figure 2: Corner weld strength of w
Page 7 and 8: TYRIN CPE in Pipes The vast majorit
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