Preparation of Monodisperse Polylactide Microspheres by Dispersion Polymerization Using a Polymeric Stabilizer with Hydroxy Groups

Abstract

Monodisperse poly(D,L-lactide) (PDLLA) microspheres have been prepared by dispersion polymerization of D,L-lactide with a synthetic polymeric stabilizer. The polymerization is carried out in xylene/heptane (1:2, v/v) at 368 K for 3 h with poly[(dodecyl methacrylate)-co-(2-hydroxyethyl methacrylate)] (P(DMA-co-HEMA)). P(DMA-co-HEMA) has hydroxy groups as an initiation group for pseudoanionic dispersion polymerization. The particle diameter and the coefficient of variation concerning the diameter distribution of the obtained PDLLA microspheres are 3.9 µm and 4.3%, respectively. In addition, from the results of dynamic light scattering measurements, it is found that P(DMA-co-HEMA) and the PDLLA-grafted copolymer form a micellar structure in solution.

Consensus equals mediocrity. There, I said it!

“…We examined the polymerization of GMA accompanied by CO 2 fixation in DOX, which is a poor solvent for polyDOMA, in the presence of CA and PVP as polymeric dispersion stabilizers33–37 (3 wt % to DOX) (Scheme and Runs 1 and 2 in Table 1). AIBN (3 mol % to GMA) and Bu 4 NCl (3 mol %) were used as the initiator and the catalyst for CO 2 fixation, respectively.…”

Preparation of Monodisperse Dye-Doped Copolymer Spheres for Photonic Crystals

“…Monodisperse polymer particles have been synthesized using different polymerization methods such as emulsion polymerization [10], dispersion polymerization [11,12], suspension polymerization [13], and soap-free emulsion polymerization [14][15][16][17]. Among these methods, soap-free emulsion polymerization is the simplest method for synthesizing monodisperse polymer particles with a self-assembling properties, which can then be used for fabricating photonic crystals.…”

Dispersion polymerization of acrylamide with water‐soluble chitosan as the stabilizer

“…The polymerization proceeds in the reaction medium until a critical molecular weight for the solubility of the polymer chain, and then the precipitated primary particles are stabilized by a polymeric stabilizer to form stable particle nuclei. Once particles have been formed, they absorbed monomer from the continuous phase and the reaction mainly took place within the particles 6–9. It has been well reported about dispersion polymerization of cationic PAM with poly(dimethylaminoethyl methacrylate methyl chloride), poly(acryloyl‐oxyethyl trimethyl ammonium chloride), poly(2‐acrylamido‐2‐methyl‐propanesulfonic acid) etc, as the stabilizer 10–14…”

“…Once particles have been formed, they absorbed monomer from the continuous phase and the reaction mainly took place within the particles. [6][7][8][9] It has been well reported about dispersion polymerization of cationic PAM with poly(dimethylaminoethyl methacrylate methyl chloride), poly(acryloyl-oxyethyl trimethyl ammonium chloride), poly(2-acrylamido-2-methylpropanesulfonic acid) etc, as the stabilizer. [10][11][12][13][14] Presently, we developed a method for preparing cationic PAM dispersion using acrylamide (AM) as the mainly raw material and dimethylaminoethyl methacrylate methyl chloride (DMC) as the cation comonomer in ammonium chloride (AC) medium.…”