TY - JOUR
T1 - Positron annihilation study in inorganic-polymer nano-composites
AU - Chen, H. M.
AU - Jean, Y. C.
AU - Lee, L. James
AU - Yang, Jintao
AU - Huang, James
PY - 2009
Y1 - 2009
N2 - Positron annihilation lifetime experiments in a series of polystyrene (PS) nano-composites of different wt% of SiO2 as a function of temperature have been performed and the glass transition temperatures are determined. Previously, in PS/CNF(carbon nanofiber), a system with strong interfacial bonding, we found single glass transition temperature (Tg), which increases with wt % of CNF. Currently, in PS/SiO2 nano-composites, a weak interfacial interaction system, we found that there are two Tgs, one at 57 °C, which is lower than the PS bulk Tg (= 91 °C). The lower Tg is interpreted from the free volume in the weak bonding interface between PS and SiO2. This result is consistent with our previous slow positron beam results of PS on Si substrate, which shows a significant lower Tg in the interface than in the bulk PS.
AB - Positron annihilation lifetime experiments in a series of polystyrene (PS) nano-composites of different wt% of SiO2 as a function of temperature have been performed and the glass transition temperatures are determined. Previously, in PS/CNF(carbon nanofiber), a system with strong interfacial bonding, we found single glass transition temperature (Tg), which increases with wt % of CNF. Currently, in PS/SiO2 nano-composites, a weak interfacial interaction system, we found that there are two Tgs, one at 57 °C, which is lower than the PS bulk Tg (= 91 °C). The lower Tg is interpreted from the free volume in the weak bonding interface between PS and SiO2. This result is consistent with our previous slow positron beam results of PS on Si substrate, which shows a significant lower Tg in the interface than in the bulk PS.
UR - http://www.scopus.com/inward/record.url?scp=72449198063&partnerID=8YFLogxK
U2 - 10.1002/pssc.200982136
DO - 10.1002/pssc.200982136
M3 - Conference article
AN - SCOPUS:72449198063
SN - 1862-6351
VL - 6
SP - 2397
EP - 2400
JO - Physica Status Solidi (C) Current Topics in Solid State Physics
JF - Physica Status Solidi (C) Current Topics in Solid State Physics
IS - 11
T2 - 15th International Conference on Positron Annihilation, ICPA-15
Y2 - 18 January 2009 through 23 January 2009
ER -