Pressure-induced polymerization of acrylic acid: a Raman spectroscopic study.

摘要: We report here the first in-situ Raman spectroscopic study of pressure-induced structural and polymeric transformations acrylic acid. Two crystalline phases (I II) were observed upon compression to ∼0.3 ∼2.7 GPa. Phase I can be characterized with a single s-cis molecular conformation possibly similar structure low-temperature phase, while phase II suggests significantly enhanced interactions toward polymerization disordering. Beyond ∼8 GPa, features indicate onset polymerization. The high-pressure together pressure-quenched materials was examined compared two commercial acid polymers using spectroscopy. characteristics their transformation mechanisms as well implications hydrogen-bonding are discussed.