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Optimization of Microencapsulation Process for
Self-Healing
Polymeric Material
(Pengoptimuman Proses
Mikro-pengkapsulan untuk Bahan Polimer Penyembuhan-Sendiri)
Sonja
Then* & Gan Seng Neon
Department
of Chemistry,Faculty of Science, University of Malaya
50603
Kuala Lumpur, Malaysia
Noor
Hayaty Abu Kasim
Department
of Conservative Dentistry, Faculty of Dentistry
University
of Malaya, 50603 Kuala Lumpur, Malaysia
Diserahkan:
23 Oktober 2009 / Diterima: 28 Julai 2010
ABSTRACT
A
series of poly(urea-formaldehyde) (PUF) microcapsules filled with
dicyclopentadiene (DCPD) was successfully prepared by in
situ polymerization. The effect of diverse process parameters and ingredients
on the morphology of the microcapsules was observed by SEM,
optical microscopy (OM) and digital microscopy. Different
techniques for the characterization of the chemical structure and the core
content were considered such as FT-IR and 1H-NMR as
well as the characterization of thermal properties by DSC.
High yields of free flowing powder of spherical microcapsules were produced.
The synthesized microcapsules can be incorporated into another polymeric host
material. In the event the host material cracks due to excessive stress or
strong impact, the microcapsules would rupture to release the DCPD,
which could polymerize to repair the crack.
Keywords:
Microcapsules; micro-cracking; in situ polymerization; self-healing material
ABSTRAK
Siri
mikrokapsul poliurea-formaldehid (PUF) yang mengandungi disiklopentadiena
(DCPD)
berjaya disediakan melalui proses pempolimeran in situ. Kesan kepelbagaian
parameter proses dan bahan reaktan terhadap morfologi mikrokapsul telah
diperhatikan melalui SEM, mikroskop optik (OM)
dan mikroskop digital. Pelbagai kaedah seperti FT-IR dan 1H-NMR diguna
untuk mencirikan struktur kimia serta kandungan teras mikrokapsul. Selain itu,
sifat terma mikrokapsul juga dianalisis menggunakan DSC.
Sfera mikrokapsul yang terhasil adalah dalam bentuk serbuk putih dengan peratus
hasilan yang tinggi. Mikrokapsul ini boleh digabungkan ke dalam bahan polimer
hos yang lain. Apabila bahan induk retak akibat tekanan yang berlebihan atau
impak yang kuat, mikrokapsul akan pecah dan membebaskan DCPD untuk
membaiki keretakan melalui proses pempolimeran.
Kata kunci: Bahan
penyembuhan-sendiri; keretakan-mikro; mikrokapsul; pempolimeran in situ
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*Pengarang untuk surat-menyurat; email:
sonja@siswa.um.edu.my
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