Claims
- 1. A toughened blend comprising:
- a. 100 parts of a polymer comprising at least 80 weight percent of units derived from vinyl chloride;
- b. from 2 to 30 parts of a multi-stage impact modifier, wherein the first stage of the multi-stage impact modifier comprises from 80 to 95 weight percent of the total stages, the first stage comprising
- 1. from 60 to 80 weight percent of units derived from butyl acrylate,
- 2. from 20 to 40 weight percent of units derived from 2-ethylhexyl acrylate,
- 3. from 0.5 to 1.2 weight percent of units derived from a monomer containing at least two non-conjugated copolymerizable carbon-carbon double bonds of the structure
- CH.sub.2 .dbd.CH--C(O)--O--, CH.sub.2 .dbd.C(CH.sub.3)--C(O)--O, or CH.sub.2 .dbd.CH--CH.sub.2 --O--
- and wherein the final stage of the multi-stage impact modifier is a copolymer containing at least 80 weight percent of units derived from methyl methacrylate; wherein all stages of the multi-stage impact polymer are prepared by emulsion polymerization; and
- wherein the toughened blend exhibits superior resistance to impact in comparison to control blends of identical composition and particle size, except that the first-stage of the multi-stage impact modifier of the control blend contains substantially 100 weight percent of units derived from butyl acrylate or contains substantially 100 weight percent of units derived from 2-ethylhexyl acrylate.
- 2. The blend of claim 1 wherein the polymer of vinyl chloride is a homopolymer of vinyl chloride.
- 3. The blend of claim 1 wherein the final stage of the multi-stage impact modifier is substantially a homopolymer of methyl methacrylate.
- 4. The blend of claim 1 wherein the final stage of the multi-stage impact modifier is a polymer of methyl methacrylate with a co-monomer containing at least two non-conjugated copolymerizable carbon-carbon double bonds present at from 0.3 to 1.0 weight percent.
- 5. The blend of claim 1 wherein the particle size of the first stage (as determined by photon correlation spectroscopy), is less than 400 nm, and wherein the first stage copolymer comprises 85-92 weight percent of the total stages.
- 6. The blend of claim 1 wherein the final stage further contains from 0.05 to 1.0 weight percent of polymerized units of a mercaptan chain transfer agent.
- 7. The blend of claim 1 in the form of an extruded or injection-molded article.
Parent Case Info
This application is a continuation-in-part of U.S. application Ser. No. 08/300,851, filed Sep. 8, 1994 abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1202155 |
Feb 1968 |
GBX |
Non-Patent Literature Citations (2)
Entry |
J59202246 Abstract (Derwent). |
European Search Report of 14 Dec. 1995, EP 95 30 5761. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
300851 |
Sep 1994 |
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