Solid, water-dispersible plastics precursors containing isocyanate groups, a process for the production of aqueous plastics dispersions using such plastics precursors

• US 4,569,981 A
• Filed: 07/06/1981
• Issued: 02/11/1986
• Est. Priority Date: 07/18/1980
• Status: Expired due to Fees

• Current Assignee: Bayer AG
• Original Assignee: Bayer AG
• Inventors: Dieterich, Dieter, Wenzel, Wolfgang
• Primary Examiner(s): Pertilla, Theodore E.
• Application Number:
  US06/280,425
• Time in Patent Office: 1,681 Days
• Field of Search: 260/29.2 TN, 528/67, 528/68, 528/71, 528/76, 528/80, 528/83, 528/79, 528/85
• US Class Current: 528/67
• CPC Class Codes: C08G 18/0804 Manufacture of polymers containing ionic or ionogenic groups
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/2815 Monohydroxy compounds
• CPC Class Codes: C08G 18/283 Compounds containing ether groups, e.g. oxyalkylated monohydroxy compounds
• CPC Class Codes: C08G 18/4837 and other oxyalkylene units

Abstract

The present invention relates to water-dispersible plastics precursors which are solid at temperatures below about 40° C. The plastics precursors are based on isocyanate-terminated prepolymers which have been hydrophilically modified with ionic groups and/or ethylene oxide units and which contain specified amounts of isocyanate groups and --NH-- groups.

The present invention also relates to processes for preparing aqueous dispersions from the solid plastics precursors and to using the plastics precursors for cross-linking dispersed plastics containing isocyanate-reactive groups.

Claims

1. Water-dispersible plastics precursors in powder, coarse powder or particulate form which remain solid at temperatures below about 40°

C. and which contain isocyanate groups and urethane, urea and/or amide groups, characterized by

(a) and average molecular weight of less than about 20,000;

(b) a content of chemically incorporated hydrophilic groups or potential hydrophilic groups guaranteeing dispersibility in water in the form of (i) from about 4 to 180 milliequivalents per 100 g of plastics precursor of ionic groups and/or convertible into ionic groups by a neutralization reaction; and

/or (ii) from about 2 to 20%, by weight based on the weight of the plastics precursors of ethylene oxide units (--CH₂ --CH₂ --O--) incorporated in polyether chains;

(c) an isocyanate content of from about 0.2 to 18%, by weight based on the weight of the plastics precusors; and

(d) a content of from 1.3 to 13%, by weight, based on the weight of the plastis precursors of --NH-- groups in the form of urethane groups (--NH--CO--O--), urea groups (--NH--CO--NH--) and/or amide groups (--NH--CO--).