Abstracts Book - IMRC 2018

• SA6-P097
PDMS NANODOMAINS CONFINED TO AN EPOXY INCREASED
TOUGHNESS AND INDUCE TWO-GLASS TRANSITION BEHAVIOR
Adriana Reyes Mayer 1,2 , Manuela Calixto Rodriguez 2 , Estela Sarmiento Bustos 2 , Karina Santiago
Santiago 2 , Angel Romo Uribe 3
1
Centro de Caracterización e Investigación en Materiales S.A. de C.V., CeCIM, Mexico.
2 Universidad Tecnológica Emiliano Zapata del Estado de Morelos, División Académica de
Mecánica Industrial, Mexico. 3 Polymer Nanocomposites Lab, , Mexico.
A nanostructured, highly flexible and optically transparent epoxy
nanocomposite was developed reacting diglycidyl ether of bisphenol-A (DGEBA)
with amine functionalized polydimethyl siloxane (PDMS). The concentration of
PDMS varied up to 7 wt%. The nanocomposites exhibited nanodroplet
morphology with up to 180 nm diameter PDMS droplets well dispersed in the
epoxy. Strikingly, PDMS induced a threefold increase of strain at fracture and
toughness. Furthermore, hydrophobic behavior was induced by PDMS, the
water contact angle increased 72° (neat epoxy) up to 110° at 5 wt% PDMS
content. The nanoconfined droplets induced a two-glass transition behavior, an
upper Tg associated to the epoxy matrix, and lower Tg associated with an
interpenetrated shell around the PDMS nanodroplets. The mechanical and two-
Tg behavior was further studied by applying thermal annealing for periods of
time. The resulting mechanical and thermal properties are correlated with the
morphology as characterized in detail by atomic force microscopy (AFM),
scanning electron microscopy (SEM) and transmission electron microscopy
(TEM). These nanocomposites are attractive for coatings/encapsulates with
improved flexibility, toughness, optical transparency and water resistance.
Keywords: Nanocomposites, Ttoughness, Epoxy resin
Presenting authors email: armayer13@gmail.com