High solids process for preparing polymeric nanoparticles
The present invention relates to an emulsion free high solids process for preparing crosslinked polymeric nanoparticles of 1-200 nm in diameter.
1. A process for preparing polymeric nanoparticles comprising adding a solvent and reactants to a vessel and reacting said reactants to form crosslinked polymeric nanoparticles; wherein the reactants comprise monomers selected from alkyl (meth)acrylates, alicyclic (meth)acrylates, (meth)acrylamides, vinyl acetates, alkenyl (meth)acrylates, aryl (meth)acrylates, alkylaryl (meth)acrylates, amine containing (meth)acrylates, phosphorous containing (meth)acrylates, sulfur containing (meth)acrylates, vinyl aromatic monomers, (meth)acrylic acid, substituted ethylene monomers and combinations thereof; wherein the reactants also comprise a crosslinker; wherein said polymeric nanoparticles have a mean particle diameter of from 1 to 50 nm wherein the process is emulsion free and wherein the process yields a solids level of polymeric nanoparticles equal to or greater than 45 weight %.
2. The process according to claim 1 wherein the process is selected from the group consisting of a batch process, a semi continuous process, and a continuous process.
3. The process according to claim 1 wherein the process is selected from the group consisting of solution polymerization, dispersion polymerization, suspension polymerization, and precipitation polymerization.
4. The process according to claim 1 wherein the reactants are added to the vessel in at least two aliquots.
5. The process according to claim 1 wherein the reactants further comprise functional polymers comprising reactive groups.
6. The process according to claim 1 wherein the reactants further comprise inorganic materials.
7. The process according to claim 1 wherein prior to completion of the adding of the reactants there is a time interval where no reactant is being fed.
8. The process according to claim 7 wherein the time interval is 30 seconds to 8 hours.
9. The process according to claim 1 , wherein the reaction temperature is between −30° C. and 150° C.
10. The process according to claim 1 , wherein the process is selected from a solution polymerization, dispersion polymerization, suspension polymerization and a precipitation polymerization.