US 2001/0056154 A1 · AQUEOUS DISPERSIONS CONTAINING A MIXTURE OF COPOLYMERS AND THEIR USE IN BINDERS

Abstract

The present invention relates to aqueous solutions or dispersions of copolymers A) containing a hydroxy-functional, hydrophobic copolymer I) containing 30 to 85% by weight of (meth)acrylic acid esters having C1 to C18 hydrocarbon radicals in the alcohol portion, aromatic vinyl compounds and/or vinyl esters and 5 to 45% by weight of hydroxy-functional monomers; a hydroxy- and carboxy-functional, hydrophilic-hydrophobic copolymer II) containing 4 to 20% by weight of (meth)-acrylic acid esters having C1 to C18 hydrocarbon radicals in the alcohol portion, aromatic vinyl compounds and/or vinyl esters, 4 to 15% by weight of hydroxy-functional monomers and 0.8 to 3.0% by weight of acid-functional monomers; and optionally a hydroxy-functional hydrophobic copolymer III) containing 0 to 16% by weight of hydroxy- and/or non-functional (meth)acrylic acid esters or aromatic vinyl compounds, wherein 1) the sum of Ia), Ib), IIa), IIb) IIc) and IIIa) is 100%, based on the weight of these components, 2) copolymer A) has an acid number, based on solids, of 10 to 28 mg KOH/g substance, 3) the weight percent of monomers IIc) in monomer II) is less than 25% by weight and 4) the weight percent of hydroxy-functional monomers IIb) in copolymer II) is higher than the weight percent of hydroxy-functional monomers Ib) in copolymer I). The present invention also relates to a method of preparing these dispersions or solutions of copolymers A) and to their use in binder compositions with at least one crosslinking resin selected from aminoplast resins, blocked polyisocyanates and polyisocyanates containing free isocyanate groups.

Claims18

Dependent claims

An aqueous solution or dispersion of copolymers A) comprising

I) a hydroxy-functional, hydrophobic copolymer comprising
Ia) 30 to 85% by weight of a (meth)acrylic acid ester having C1 to C18 hydrocarbon radicals in the alcohol portion, an aromatic vinyl compound and/or a vinyl ester and
Ib) 5 to 45% by weight of hydroxy-functional monomers,
II) a hydroxy- and carboxy-functional, hydrophilic-hydrophobic copolymer comprising
IIa) 4 to 20% by weight of a (meth)acrylic acid ester having C1 to C18 hydrocarbon radicals in the alcohol portion, an aromatic vinyl compound and/or a vinyl ester,
IIb) 4 to 15% by weight of a hydroxy-functional monomer and
IIc) 0.8 to 3.0% by weight of an acid-functional monomer, and
III) optionally a hydroxy-functional hydrophobic copolymer comprising
IIIa) 0 to 16% by weight of a hydroxy- and/or non-functional (meth)acrylic acid ester or an aromatic vinyl compound,
wherein
i) the preceding percentages are based on the total weight of components I), II) and III,
ii) the sum of Ia), Ib), IIa), IIb) IIc) and IIIa) is 100%, based on the weight of these components,
iii) copolymer A) has an acid number, based on solids, of 10 to 28 mg KOH/g substance,
iv) the weight percent of monomer IIc) in monomer II) is less than 25% by weight and
v) the weight percent of hydroxy-functional monomer IIb) in copolymer II) is higher than the weight percent of hydroxy-functional monomer Ib) in copolymer I).

12 more elements

A process for preparing an aqueous dispersion or solution of copolymers A) which comprises by

a) free radically copolymerizing in a solvent mixture containing 30 to 95% by weight of an unsaponifiable, water-immiscible, hydrophobic solvent and 5 to 70% by weight of an unsaponifiable, water-miscible, hydrophilic solvent a mixture comprising
Ia) 30 to 85% by weight of a (meth)acrylic acid ester having C1 to C18 hydrocarbon radicals in the alcohol portion, an aromatic vinyl compound and/or a vinyl ester and
Ib) 5 to 45% by weight of hydroxy-functional monomers,
to form a hydroxy-functional, hydrophobic copolymer I) which is essentially free from carboxyl groups,
b) subsequently free radically copolymerizing a mixture comprising
Ia) 4 to 20% by weight of a (meth)acrylic acid ester having C1 to C18 hydrocarbon radicals in the alcohol portion, an aromatic vinyl compound and/or a vinyl ester,
IIb) 4 to 15% by weight of a hydroxy-functional monomer and
IIc) 0.8 to 3.0% by weight of an acid-functional monomer, and to form a hydroxy- and carboxy-functional, hydrophilic-hydrophobic copolymer II),
c) optionally subsequently free radically copolymerizing
IIIa) 0 to 16% by weight of a hydroxy- and/or non-functional (meth)acrylic acid ester or an aromatic vinyl compound to form a hydroxy-functional, hydrophobic copolymer III),
d) neutralizing at least 70% of the carboxyl groups and
e) dissolving or dispersing copolymer A) in water,
wherein
i) the percentages of the monomers are selected such that copolymer A) contains 60 to 90% by weight of copolymer I) and 10 to 40% by weight of copolymer II),
ii) copolymer A) has an acid number, based on solids, of 10 to 28 mg KOH/g substance and
iii) the weight percent of hydroxy-functional monomer IIb) in copolymer II) is higher than the weight percent of hydroxy-functional monomer Ib) in copolymer I).

13 more elements

Dependencies are inferred from the claim text.

Aqueous dispersions containing a mixture of copolymers and their use in binders

Life of this patent

Aqueous dispersions containing a mixture of copolymers and their use in binders

Life of this patent

Abstract

Claims18