The present invention is directed to a crosslinked or non-crosslinked polymer particle, wherein the crosslinked polymer particle comprises a copolymer of poly(alkylene glycol-graft-acrylate) that is crosslinked by at least one hydrolysable monomer or crosslinking agent. The present invention is also directed to a polymer particle comprising a crosslinked polymer particle that is a product of starting materials comprising (a) a hydrophilic monomer, (b) a hydrophobic monomer, and (c) a hydrolysable crosslinking agent (the crosslinking agent may be absent in the case of non-crosslinked particles). The present invention is still further directed to a polymer particle comprising a crosslinked copolymer, where the crosslinked copolymer includes structures represented by Formulas (I), (II), and (III), as defined in the specification. Other embodiments of the present invention also include methods of manufacturing polymer particles.