Acrylic impact modifiers

Typical additive packages for engineering thermoplastics have been described by Titzschkau [9], such as processing aids for PA, PP, or PET/PBT, three-component additive packages for polyamides and polyesters (nucleating agent, lubricant and process heat stabiliser) and coated copper stabilisers for polyamides. Additive packages or combinations of up to five or more additives are quite common. A typical white window PVC profile formulation comprises an acrylic impact modifier, TiC>2, CaCC>3, calcium stearate, a... 

The PARALOID EXL range also includes PARALOID EXL 2314, an acrylic impact modifier with reactive functionality for PET impact modification. 

Acrylic impact modifier (4) Dylark Nova Chemicals S.A. 

Grafted copolymers obtained by VCM polymerisation and polyacrylic elastomer grafting, give high bulk density resins for products with high impact strength suitable for outdoor applications. The separate addition of acrylate impact modifiers to the PVC formulation is covered in Section 4.5.2. 

Brookfield, Ct., SPE, 2002, Paper 571, Session W7-Vinyl Plastics. Vinyl Composites, pp.5, CD-ROM, 012 EFFECT OF CALCIUM CARBONATE SIZE AND LOADING LEVEL ON THE IMPACT PERFORMANCE OF RIGID PVC COMPOUNDS CONTAINING VARYING AMOUNTS OF ACRYLIC IMPACT MODIFIER Bryant W S Wiebking H E Specialty Minerals Inc. 

ADAPTATION OF NEW ACRYLIC IMPACT MODIFIER TECHNOLOGY TO PVC EXTRUSION INDUSTRY TRENDS... 

Crestomer . [Scott Bader] Unsaturated urethane acrylates impact modifier enhances performance of polyester resins, comp., and laminates. 

Table 15.11. Commercial acrylic/impact modifier blends vs. acrylic...

Blend Type ACRYLIC/IMPACT MODIFIER ACRYLIC... 

Figure 2.31. Izod notched impact study of two types of PVC having different K numbers and variable concentration of acrylic impact modifier (Paraloid KM-334). [Data from Tseng, A. A. IBorrosky, M. A. O Connor, S. M. Knotts, J. J., Adv. Polym. Technoi, 10, 3,205-218, 1990.]...

Figure 3.12. Impact strength of PVC containing 5 phr acrylic impact modifier and variable amounts of calcium carbonate. [Data from Wiebking, H. E., J. Vinyl Additive Technol,2,3, 187-189,1996.]...

A study shows that the use of acrylic impact modifier also permits the improvement of impact resistance with the addition of calciiun carbonate (Figure... 

Predesigned particles of impact modifiers are based on core-shell technology. Core is involved in impact modification and shell improves adhesion between PVC and impact modifier particles.Three major combinations are used methacrylate-butadiene-styrene, MBS, which has a core made out of butadiene-styrene copolymers and shell made out of methylmethacrylate-styrene copolymer, acrylic impact modifiers, AIM, which have a core made out of acrylic and shell from polymethylmethacrylate, and silicone-acrylic have multilayer structures with silicone-acrylic in the core. MBS has excellent compatibility with PVC, similar to ABS, which is used as an impact modifier of PVC, as well. In both cases of ABS and MBS, weather resistance is lacking, therefore they are used for indoor applications only. At the same time, MBS gives translucent to crystal clear products, whereas with AIM, only translucent products are possible. In order to improve optical properties of AIM, it has to be reformulated. For transparent products, the core is made out of acrylic-styrene copolymers. Comparing silicone and all acrylic impact modifiers, PVC containing silicone-based products has superior low temperature impact properties. The incorporation of silicone into an acrylic impact modifier provides excellent weatherability, and thermal stability. It has shown improved retention of impact after outdoor weathering in PVC. ... 

Figure 3.28. Impact strength of PVC containing Figure 3.29. Impact strength vs. concentration 8 phr acrylic impact modifier vs. shell thickness of impact modifier. [Data from Stevenson, J. C. of modifier. [Data from Lee, J.-S. Chang, F.-C., Fazey, A. C., J. Vinyl Additive TechnoL, 3,2, Polym. Eng. ScL, 44,10,1885-1889,2004.] II8-I25, 1997.]...

The addition of talc increases the flexural modulus at elevated temperature, which leads to improved dimensional stability. Use of high concentration of ultrafme talc with precipitated calcium carbonate and acrylic impact modifier permits increase of dimensional stability and high impact strength. 

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