Synthesis and characterization of novel acid-sensitive tert-butyl methacrylate and isobutyl methacrylate containing star-shaped polymers

Timothy Edward Long, Lars Kilian, Zhen He Wang, Alan R. Esker

Research output: Contribution to journalConference article

4 Citations (Scopus)


Star-shaped polymers containing poly(isobutyl methacrylate) (iBMA) and poly(tert-butyl methacrylate) (t-BMA) arms coupled to a 2,5-dimethyl-2,5-hexanediol dimethacrylate (DHDMA) core were synthesized using arm-first living anionic polymerization. Gel permeation chromatography (GPC) indicated that coupling efficiencies were high and coupled products exhibited a monomodal molecular weight distribution. The star-shaped polymer number-average molecular weights were 8-10 times higher than the precursor arm molecular weights. The ratio of coupling reagent to living chain end concentration controlled the molecular weight of the star-shaped polymer and the number of coupled arms. The molecular weight distributions of the star-shaped polymers ranged from 1.5-2.0. Due to the labile tertiary-butyl esters contained in the DHDMA cores, these star-shaped polymers were readily hydrolyzed in the presence of acid catalysts. For example, poly(iBMA) star-shaped polymers were hydrolytically stable at 25 °C and hydrolyzed readily at 65 °C in the presence of hydrochloric acid. In addition, the poly(t-BMA) containing star-shaped polymers degraded under similar conditions. The degradation process for the iBMA and t-BMA containing star-shaped polymers was confirmed using 1H NMR spectroscopy, and poly(iBMA)-block-poly(methacrylic acid) and poly(methacrylic acid) were obtained, respectively.

Original languageEnglish
Pages (from-to)65-74
Number of pages10
JournalProceedings of SPIE - The International Society for Optical Engineering
Publication statusPublished - 2001 Dec 1
Externally publishedYes
EventComplex Adaptive Structures - Hutchinson Island, FL, United States
Duration: 2001 Jun 42001 Jun 6



  • Anionic polymerization
  • Coupling
  • Degradable
  • Hydrolysis
  • Methacrylate
  • Star-shaped polymer
  • Synthesis

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this