Medium density chlorinated polyvinyl chloride foam and process for preparing

• US 6,348,512 B1
• Filed: 09/30/1996
• Issued: 02/19/2002
• Est. Priority Date: 12/29/1995
• Status: Expired due to Fees

• Current Assignee: Noveon, Inc. (Berkshire Hathaway Incorporated)
• Original Assignee: PMD Holdings Corporation
• Inventors: Adriani, Paul M.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US08/722,703
• Time in Patent Office: 1,968 Days
• Field of Search: 521/85, 521/91, 521/92, 521/93, 521/134, 521/139, 521/145
• US Class Current: 521/85
• CPC Class Codes: C08J 2205/08 Semi-flexible foams
• CPC Class Codes: C08J 2327/06 Homopolymers or copolymers of vinyl chloride
• CPC Class Codes: C08J 9/0014 Use of organic additives
• CPC Class Codes: C08J 9/0052 Organo-metallic compounds
• CPC Class Codes: C08J 9/10 developing nitrogen , the blowing agent being a compound containing a nitrogen-to-nitrogen bond

Abstract

The present invention relates to a medium density chlorinated polyvinyl chloride foam and the method of preparing such a foam. The foam having a specific gravity in the range of about 0.3 to about 1.5 comprises chlorinated polyvinyl chloride, a nitrogen containing decomposition type blowing agent, a tin stabilizer, a costabilizer and a high molecular weight process aid.

Claims

1. A medium density chlorinated polyvinyl chloride foam having a specific gravity in the range of about 0.3 to 1.5 comprising chlorinated polyvinyl chloride having a chlorine content of at least sixty percent (60%), a nitrogen containing decomposition type blowing agent, a tin stabilizer, a costabilizer selected from a member of the group consisting of disodium hydrogen phosphate, hydrotalcite, alkali citrates, aluminum magnesium hydroxy carbonate hydrate, magnesium aluminum silicate, and alkali alumino silicates, and a high molecular weight process aid and, optionally lubricant(s) and/or metal release agent(s).

2. A medium density chlorinated polyvinyl chloride foam of claim 1, wherein said nitrogen containing decomposition blowing agent comprises p-toluene sulfonyl-semicarbazide, p,p-oxybis benzene sulfonyl hydrazide, azodicarbonamide, 5-phenyltetrazole, dinitrosopentamenthylenetetramine, and mixtures thereof.

3. A medium density chlorinated polyvinyl chloride foam of claim 2, wherein said nitrogen containing decomposition blowing agent comprises azodicarbonamide.

4. A medium density chlorinated polyvinyl chloride foam of claim 3, wherein said azodicarbonamide is added in the range of about 0.1 to about 10 parts by weight for every 100 parts by weight of chlorinated polyvinyl chloride.

5. A medium density chlorinated polyvinyl chloride foam of claim 1, wherein said tin stabilizer is chosen from the group comprising:

stannous maleate, dibutyltin dilaurate, dibutyltin maleate, di(n-octyl) tin maleate, dibutyltin bis(lauryl mercaptide), dibutyltin S,S-bis(isooctyl thioglycoate), dibutyltin β

-mercaptoproprionate, di-n-octyltin S,S-bis(isooctyl thioglycolate), and di-n-octyltin β

-mercaptoproprionate.

6. A medium density chlorinated polyvinyl chloride foam of claim 5, wherein said tin stabilizer is dibutyltin S,S-bis (isooctyl) thioglycolate.

7. A medium density chlorinated polyvinyl chloride foam of claim 5, wherein said tin stabilizer is added in the range of about 1 to about 5 parts by weight per 100 parts by weight of the chlorinated polyvinyl chloride.

8. A medium density chlorinated polyvinyl chloride foam of claim 1, wherein said costabilizer comprises disodium hydrogen phosphate.

9. A medium density chlorinated polyvinyl chloride foam of claim 1, wherein said high molecular weight process aid has a weight average molecular weight greater than 1,000,000 grams/mole.

10. A medium density chlorinated polyvinyl chloride foam of claim 1 wherein said high molecular weight process aid comprises a copolymer of styrene acrylonitrile or an acrylic processing aid.

11. A medium density chlorinated polyvinyl chloride foam of claim 10, wherein said high molecular weight process aid comprises an acrylic process aid.

12. A medium density chlorinated polyvinyl chloride foam of claim 11, wherein said acrylic process aid comprises polymethyl methacrylate.

13. A medium density chlorinated polyvinyl chloride foam of claim 10, wherein said high molecular weight process aid comprises a copolymer of styrene acrylonitrile.

14. A medium density chlorinated polyvinyl chloride foam of claim 1, further comprising chlorinated polyethylene.