Arkema France

Atofina

Arkema Inc.

Arkema Coatings Resins S.r.l.

Mario Lugli

Leo Mario Saija

Daniele Becchi

Umberto Amadei

Wenjun Wu

Stefano Finocchiaro

Simona Ferretti

Hua Zhou

Xiangling Meng

Haiming Chen

Flippo Finetti

Luca Resta

Andrea Premoli

Leo Saija

Leo-Mario Saija

The invention relates to aqueous polymer dispersions stable for at least 12 h, when dissolved in high amount of organic solvents and acidified at low pH (pH<2). The polymer comprises units and/or groups issued from: a) at least one (meth)acrylic monomer which is (meth)acrylic ester of a C1-C12 alcohol without any other functional group than (meth)acrylate, b) at least monomer b1) or initiator b2) or both as defined: b1) at least one vinylic, allylic or (meth)acrylic monomer, bearing an anionic group derived from strong acids with pKa<3, b2) at least one initiator, bearing the same anionic group as b1), c) at least one hydroxy-functional vinylic, allylic or (meth)acrylic monomer, and optional monomers, and which polymer bears: the anionic groups as defined in b) in an amount of at least 0.05 meq/g and hydroxy groups as defined in c) in an amount of at least 0.1 meq/g.

Stable aqueous polymer dispersions

The invention relates to aqueous polymer dispersions comprising polymerized units issued from the following monomers with related weight proportions based on 100 parts of weight of a)+b): a) 50 to 90% of a monoethylenically unsaturated non-ionic monomer, b) 10 to 50% of vinyl aromatic monomer or methyl methacrylate, c) 1 to 5% of a hydroxy-containing (meth)acrylate, d) 0.1 to 3% of acid monomer selected from d1) acid monomer selected from monocarboxylic or dicarboxylic acid monomers and d2) acid monomer selected from phosphorous-based or sulfur-based strong acid monomers or/and their salts, or from the mixtures of d1) and d2), e) 0.001 to 0.5% of chain transfer agent, and f) 0 to 1% one of internal crosslinker bearing at least two copolymerisable ethylenic unsaturations, the polymer having a Tg measured by DSC from −30 to 0° C. and a gel content of 0 to 60%, formed during polymerization.

Emulsion polymer compositions and use thereof in low odor waterproofing coatings

The invention relates to an aqueous polymer dispersion comprising:

Pressure sensitive compositions based on a modified rubber polymer aqueous dispersion

The process comprises the following phases: formation of a pre-emulsion of monomers in water; transfer into the polymerisation reactor with stirring, of (1) reaction stock consisting of a water solution of a surfactant, in an amount by weight relative to the weight of final polymer dispersion of 1&#x2013;15%; (2) a portion of the pre-emulsion prepared in the previous phase, in an amount of 1%&#x2013;10% by weight of the initial pre-emulsion; phase C.1: initiation of the polymerisation ; phase C.2: polymerisation of the monomer mixture at 30&#x2013;90&#xb0; C., by gradually adding into the reactor, separately, the initiator solution and the remaining portion of the pre-emulsion with an added salt, which is soluble in water at 25&#xb0; C. to at least 1% by weight, in an amount so as to have a salt concentration in the added pre-emulsion of 0.02&#x2013;0.25% by weight; phase C.3: scrubbing of the residual monomers.

Process for obtaining aqueous polymer dispersions

Aqueous polymer dispersions

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Fabbrico, Italy

Mario Lugli