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Production of ultrafine suspensions of bisphenol, sodium hydroxide and water

  • US 5,275,758 A
  • Filed: 09/01/1992
  • Issued: 01/04/1994
  • Est. Priority Date: 09/05/1991
  • Status: Expired due to Term
First Claim
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1. A process for the production of ultrafine suspensions based on 2,2-bis- )-propane (=bisphenol A, "BPA"), sodium hydyroxide and water, characterized in thata) a melt of bisphenol A is combined with sodium hydroxide and water with intensive mixing (mixing energy 0.5 watt/liter),b) a temperature of at least 60°

  • C. and at most 90°

    C. being established in at most 1 minute after mixing, optionally by cooling, andc) the ratios of bisphenol A to NaOH are selected so that between 1.5 and 2.2 mol NaOH are used per mol bisphenol A and 15 parts by weight to 40 parts by weight of the sum of BPA and NaOH are present per 100 parts by weight water andd) at most 50% of the BPA used, optionally in the form of its alkali metal salt, are precipitated at those temperatures ande) the aqueous solution is subsequently cooled with further vigorous mixing (mixing energy>

    0.5 watt/liter) to temperatures of 10 to 35°

    C. in times of 1 second to 30 minutes, an opaque ultrafine suspension being formed.

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