Method of manufacturing water-soluble polymer dispersions having high polymer content

US5541252A · kind A · utility

Assignee

• Rohm Co., Ltd. · JP

Inventors

• Gunter Schmitt · Darmstadt, DE
• Joachim Carl · Stein, DE
• Manfred Braum · Mainz, DE
• Peter Quis · Darmstadt, DE
• Petra Schliessmann · Darmstadt, DE

Key dates

• Filing date: Apr 12, 1995
• Grant date: Jul 30, 1996
• Expiry date: Apr 12, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2300/14
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a process for the preparation of low viscous, water soluble polymer dispersions on an aqueous basis with a high concentration of the active substance, containing a polymerizate A) synthesized from the monomeric components, hydrophobic monomers and optionally amphiphilic monomers, which exhibit an average molecular weight M.sub.w of at least 5.times.10.sup.5 Dalton and contain at least one polymeric dispersing agent D), where in a first step an aqueous dispersion PD) is prepared from the polymerizate A) and at least one polymeric dispersing agent D); in a second step an aqueous, highly concentrated dispersion PD') is prepared from the aqueous dispersion PD) by extracting the water; and in a third step an aqueous dispersion PD") with a high content of the active substance is prepared through the addition of an aqueous dispersion of at least one polymeric dispersing agent D) to the concentrated dispersion PD'), and where the second and third process step can be repeated in succession.