Microstructural Characterization and Thermal Analysis of Block Copolymer of Methyl Methacrylate and n-Butyl Acrylate

Abstract

Microstructural characterization of synthetic copolymers can be employed to establish structure-property relationships for various practical applications. Acrylic copolymers are economical and suitable for processing into interesting materials for diverse applications. The relative composition, sequence distribution, and configuration of block copolymer monomeric units of poly(methyl methacrylate-b-n-butyl acrylate) (PMMA-b-nBA) was studied by the combination of Fourier transform-infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, and modulated differential scanning calorimetry (MDSC). Configurational assignments of MMA and BA blocks were determined from ¹³C NMR and heteronuclear single-quantum correlation spectroscopy (HSQC), respectively. The α-carbon resonances from methacrylic units appear from downfield to upfield in the order mm, rm/mr, rr, whereas they appear in the opposite order in acrylic units.

Keywords:

• Block copolymer
• FT-IR
• MDSC
• Methyl methacrylate
• Microstructure
• n-Butyl acrylate
• NMR

Acknowledgments

Dr. M. Monroy-Barreto thanks ICyTDF for a postdoctoral scholarship.

Notes

ND: not detected.

Determined from (a) ¹³C and (b) HSQC NMR spectra.

*Data obtained from heavily overlapped peak.