Third Day Poster Session, 17 June 2010 - NanoTR-VI

Poster Session, Thursday, June 17
Theme F686 - N1123
UV CURABLE B/F/Si CONTAINING HYBRID MATERIALS
Bihter Zeytuncu, 1* M.Vezir Kahraman 2 and Onuralp Yucel 1
1 Applied Research Center of Materials Science and Production Technology, Istanbul Technical University, Istanbul 34469, Turkey
2 Department of Chemistry, Marmara University, Istanbul 34722, Turkey
Abstract — A series of UV-curable boron/flour/silicon containing hybrid coatings prepared by anhydrous sol-gel technique.
The chemical structure of hybrid coatings was characterized by FT-IR, RT-IR, 1 H-NMR and 29 Si-CP MAS-NMR techniques.
UV curable coatings were applied on polycarbonate substrates. The physical and mechanical properties of UV-cured coatings
such as pendulum hardness, pencil hardness, contact angle, gel content, MEK rubbing test, tensile test, abrasion resistance,
chemical resistance, flame retardant, anti-stain and gloss were examined. Thermal gravimetric analysis (TGA) was made.
Results of all analysis conducted on free films and coatings were discussed. The morphology of the hybrid materials was
examined by SEM. The hybrids were nanocomposites.
Sol-gel is widely used method for the preparation of
organic-inorganic hybrid based coating materials [1].
Organic-inorganic hybrid materials combine the
advantages of either elasticity, impact resistance of organic
polymers and the high mechanical strength, chemical
resistance, thermal stability, optical qualities of the
inorganic materials. The UV curable hybrid coatings
prepared by sol-gel method, have low cost, fast curing, low
viscosity and long time duration [2,3]. The UV curable
hybrid coating materials have good adhesive, hardness,
good mechanical and chemical properties, which are
sensitive to the environment [4].
The aim of this study was to prepare and characterize
UV-curable, boron/flour/silicon-containing epoxy acrylate
based organic-inorganic hybrid coatings having abrasion
and flame resistant, anti-stain and high gloss properties.
Therefore, in the first stage; borate ester was synthesized.
Then, hybrid coatings having various concentrations of
boron/flour/silicon were prepared and applied on to
Polycarbonate panels and were hardened by UV
irradiation. The prepared hybrid coatings were
characterized by the analysis of various properties such as
hardness, abrasion and chemical resistance, flame
retardancy, gloss and stress–strain tests. The thermal and
morphological behavior of the hybrid coatings was also
evaluated.
The solvent resistance of coatings was examined by
performing the MEK rubbing test. The solvent resistance
is excellent; exceeding 500 MEK double rubs while pencil
hardness is greater than 5H, also indicative of highly crosslinked
film. The gel content of polymeric films was found
to be between 98 to 99,7 %. The cross-cut adhesion
experiment showed that 100 % adhesion was reached for
all coatings. The chemical resistance of all hybrid coatings
was also investigated by immersing samples in various
reagents (10 % NaOH, 10 % HCl, 10 % H 2 SO 4 , Xylene)
for 24 h time period. The general physical appearance of
samples was perfect and no cracks were observed.
Abrasion resistance is often characterized by the Taberabraser
method measuring the mass decrease caused by the
mechanical degradation of protective layers that is treated
by abrading grinders. The high boron/flour/silicon content
demonstrated a better protective performance in
comparison to other formulations. The LOI values of these
coatings increased from 20.4 to 23.1. The thermal
oxidative stability of the hybrid coating was investigated
by thermo gravimetric analysis (TGA) technique in air
atmosphere. The maximum weight loss temperature was
raised to 425 ◦C. The enhancement of incorporation of
B/F/Si on the thermal stability of epoxyacrylate resins was
thus demonstrated. Therefore it is concluded that the
thermal stability of epoxy acrylate resin is enhanced by
adding B/F/Si as a flame retardant. The morphology of the
fractured surfaces was observed by scanning electron
microscopy (SEM). Figure 1 presents the SEM image of
the hybrid coating material. The SEM micrograph show
spherical borosilicate particles are distributed within the
hybrid system. The approximate particle size is less than
100 nm.
Figure 1: SEM micrograph of the hybrid coating
In summary, UV curable boron containing organicinorganic
hybrid coating was prepared by anhydrous solgel
technique. The properties of boron-containing hybrid
coating materials such as hardness, chemical and abrasion
resistance were improved. All hybrid coatings were
obtained crack free and transparent. The solvent and
chemical resistance experiments proved that all the hybrid
materials are promising as a candidate for the related
applications. On the other hand thermal and flameretardant
properties of hybrid coatings were improved by
the increasing of B/F/Si content. The morphology studies
indicate that, the nanometer-scaled inorganic particles
disperse homogenously in the hybrid system.
*Corresponding author: bihter_zeytuncu@hotmail.com
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and Chemistry of Sol-Gel Processing"; Academic Press, New
York, USA, (1990).
[2] Holman, R.; Oldring, P.; “UV& EB curing formulation for
printing inks, coatings and paintings”, London (1998).
[3] Odian, G.: "Principles of Polymerization"; Fourth Edition;
Wiley Interscience, New York, USA, (2004) 96.
[4] Cho, J:; Kim, E.; Kim, H.K.; Hong, J.: “An investigation of
the surface properties and curing behaviour of photocurable
cationic films photosensitized by anthracene” Polymer Testing,
21 (2002) 781.
[5] Kahraman, M.V., Boztoprak,Y., Güngör, A., Apohan, A.K.,
Progress in Organic Coatings 66 (2009) 52–58.
6th Nanoscience and Nanotechnology Conference, zmir, 2010 707