Phosphinic acid aluminum salts

• US 6,211,402 B1
• Filed: 02/16/1999
• Issued: 04/03/2001
• Est. Priority Date: 07/22/1996
• Status: Expired due to Term

• Current Assignee: Celanese Sales Germany GmbH (Celanese Corporation)
• Original Assignee: Ticona GmbH (Celanese Corporation)
• Inventors: Kleiner, Hans-Jerg
• Primary Examiner(s): Vollano, Jean F.
• Application Number:
  US09/214,473
• Time in Patent Office: 777 Days
• Field of Search: 556/174, 556/13, 562/22, 562/8, 562/21, 562/20
• US Class Current: 562/8
• CPC Class Codes: C07F 17/02 of metals of Groups 8, 9 or 10 of the Periodic Table
• CPC Class Codes: C07F 9/30 Phosphinic acids [R2P(=O)(OH)]; Thiophosphinic acids ; [R2P(=X1)(X2H) (X1, X2 are each independently O, S or Se)]
• CPC Class Codes: C08K 5/5313 Phosphinic compounds, e.g. R2=P(:O)OR'

Abstract

Aluminum salts of phosphinic acid or diphosphinic acids having alkyl and/or aryl substitutes, obtainable by heating an ester of the corresponding phosphinic acids or diphosphinic acids with aluminum hydroxide at a temperature of more than 150° C. under pressure in the presence of water, are distinguished by a particular crystal structure and are suitable as flameproofing agents for plastics.

Claims

1. A process for the preparation of high temperature modification aluminum salts of phosphinic acids or diphosphinic acids, which comprises reacting esters of the corresponding phosphinic acids or diphosphinic acids with aluminum hyroxide under pressure at 150 to 350°

C. in the presence of water.

5. A process for the preparation of high temperature modification aluminum salts of phosphinic acids or diphosphinic acids, which comprises exposing an aluminum salt prepared by low temperature modification to temperatures in the range from 150 to 350°

C., under pressure and in the presence of water and wherein said low temperature modification is at temperatures of 100°

C. or less.

2. The process as claimed in claim 6, wherein said phosphoric esters or diphosphonic esters are the formula (III) or (IV)

in which

R¹ and R² are identical or different and are a C₁-C₈-alkyl or phenyl,

R³ is a C₁-C₁₀-alkylene, an arylene, an alkylarylene, an arylalkylene, and

R⁴ is a C₁-C₈-alkyl.

3. The process as claimed in claim 2, wherein R¹ and R² are identical or different and are an ethyl, methyl, n-propyl, isobutyl, n-butyl, n-hexyl or phenyl, R³ is methylene, ethylene, n-propylene, isopropylene, n-butylene, n-decylene, phenylene, napthylene, methylphenylene, ethylphenylene, methylphenylenemethyl, phenylenemethylene or phenylethylene R⁴ is a C₄-C₆-alkyl.

4. The process as claimed in claim 3, wherein said temperature is from 180°

to 250°

C. for a period of 50 to 70 hours.

6. The process as claimed in claim 5, wherein said exposing is for a period of more than 40 hours.