Confined space crystallisation of poly(epsilon-caprolactone) in controlled pore glasses
2013 (English)In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 49, no 8, 2073-2081 p.Article in journal (Refereed) Published
A series of controlled pore glasses (CPGs) with pore diameters ranging from 10 nm to 293 nm were impregnated with three poly(epsilon-caprolactone)s (PCL) differing in number average molar mass (10-80 kDa), and their crystallisation kinetics were studied with differential scanning calorimetry. Scanning electron microscopy and thermogravimetry confirmed that the polymers were mainly housed within the pore channels. The PCLs housed in the CPG with the finest pores (10 nm) showed a markedly different crystallisation behaviour from that of the corresponding bulk pristine polymers: a significantly slower crystallisation, a low Avrami exponent (<1), a higher product of the surface free energies of the fold and lateral surfaces of the formed PCL crystals and a lower initial melting peak temperature. This behaviour of confinement was similar for the three PCLs studied. In the CPGs with wider pore channels (23-293 nm), the PLCs showed essentially the same crystallisation kinetics as the pristine polymers. These differences in the crystallisation kinetics were attributed to the confinement, i.e. to the small available volume with respect to crystal size and to interactions with the pore walls. The results obtained suggest that the initial stages of crystallisation, presumably including other crystal phases or mesophases, occurred according to different paths for bulk PCL and for PCL housed in narrow nanopores.
Place, publisher, year, edition, pages
2013. Vol. 49, no 8, 2073-2081 p.
Poly(epsilon-caprolactone), Controlled pore glasses, Silica aerogel, Confined crystallisation
IdentifiersURN: urn:nbn:se:kth:diva-109807DOI: 10.1016/j.eurpolymj.2013.04.034ISI: 000322503800020ScopusID: 2-s2.0-84880173550OAI: oai:DiVA.org:kth-109807DiVA: diva2:584468
FunderSwedish Research Council, 2006-3559 2009-3188
QC 20130909. Updated from submitted to published.2013-01-092013-01-092013-09-09Bibliographically approved