The
synthesis of four different monofunctional vinyl cyclopropane
(VCP) derivatives and their polymerization behavior is presented.
The different VCPs have different capabilities to form hydrogen bonds
in their side chain. A preorganization due to these hydrogen bonds
should lead to a fast polymerization. Kinetic studies, hydrogen-bond
strength, and theoretical calculations were used to correlate the
degree of conversion and the amount of preorganization. While VCPs
capable of hydrogen bonding did not show a huge difference, a general
effect of hydrogen bonds on polymerization behavior could be observed.
We use atomistic as well as coarse-grained molecular dynamics simulations to study the conformation of a single poly(3-hexylthiopene) chain as a function of temperature. We find that mainly bundle and toroid structures appear with bundles becoming more abundant for decreasing temperatures. We compare an atomistic and a Martini-based coarse-grained model which we find in very good agreement. We further illustrate how the temperature dependence of P3HT can be connected to that of simple Lennard–Jones model polymers in a vacuum. Upon adding solvent (THF) we observe the occurrence of a prominent swelling of the molecular size at a temperature of about 220 K. This swelling is in close agreement with the interpretation of recent spectroscopic experiments (Panzer et al. J Phys Chem Lett 8, 114 (2017)) which allows us to explain the experimental observations by an increased frequency of bundle structures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.