| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 봄 (04/14 ~ 04/15, 전경련회관) |
| 권호 | 30권 1호, p.220 |
| 발표분야 | 기능성 고분자 |
| 제목 | Fabrication of Poly (glycidyl methacrylate) Naoprticles Based on Microemulsion Polymerization |
| 초록 | Until now, most of researches related to well-defined polymeric materials have been focused on the utilization of thermoplastic or conducting polymers in the fields of catalyst, battery, and drug delivery. Recently, thermoset based nanomaterials have attracted an enormous interest owing to their unique properties such as chemical and physical stability, and durability. Nevertheless, the fabrication and application of thermoset polymer based nanoparticles, nanorods, or nanofibers have not been reported yet. Among various thermoset polymers, epoxy resins are especially interesting because of their excellent properties such as, low shrinkage in cure, high adhesion, and dimensional stability. Here we report on the fabrication of epoxide functionalized poly(glycidyl methacrylate) nanoparticles with a dimension of 10-15 nm prepared using microemulsion polymerization for the first time. The PGMA nanoparticles were cured with diethylenetriamine (DETA) at low temperature without coagulation and morphological transformation. The cure reaction of PGMA nanoparticles was monitored by FT-IR spectroscopy and DSC thermal analysis. Cationic surfactant such as octyltrimethylammoniumbromide (OTAB), decyltrimethylammoniumbromide (DeTAB), and dodecyltrimethylammoniumbromide (DoTAB) were used to control the size of PGMA nanoparticles. Microemulsion polymerization of GMA with OTAB produced spherical and monodispersed PGMA nanoparticles. The average diameter of the PGMA nanoparticles was approximately 12-13 nm and reasonably monodisperse. The average diameter of cured polymer nanoparticles was approximately 10-15 nm, which was consistent with that of pristine nanoparticles. Compared with pristine PGMA nanoparticles, cured nanoparticles were reasonably monodisperse and spherical. While the cure reaction was conducted just below glass transition temperature of PGMA, the regional aggregation of PGMA nanoparticles was not observed remarkably. This fact confirms that the curing temperature was suitable for curing of individual PGMA nanoparticles. In addition, morphological transformation did not occur during curing unlike conventional epoxy resin. The curing of PGMA nanoparticles without coagulation and morphological transformation also leads to the enhanced surface area and functionality. The Characteristic peaks in FT-IR spectra of PGMA nanoparticles prepared using 2 g and 3 g of OTAB show carbonyl (C=O) group at 1730 cm-1 and two vibrational bands at 966 and 912 cm-1 associated with asymmetric and symmetric epoxy ring bending. The intensities of two peaks at 966 and 912 cm-1 increased at high surfactant concentration. This result can be explained well by the fact that the number of epoxy ring in PGMA particles increases with increasing the surface area of PGMA in unit mass by reducing the size. The enhanced surface functionality indicates that PGMA nanoparticles can be applied widely instead of conventional PGMA embedded materials. To obtain cured PGMA nanoparticles, the prepared PGMA nanoparticles were cured with diethylenetriamine (DETA) which is one of strong curing agents suitable for low temperature curing reaction, since the amine groups are very reactive toward epoxide group even below 50 °C. The cure behavior was investigated with FT-IR and DSC. In this work, poly(glycidyl methacrylate) nanoparticles with a dimension of 10-15 nm were successfully synthesized using microemulsion polymerization. This is the first demonstration for fabrication of thermoset polymer nanoparticles with dimension less than 15 nm. The surfactant concentration is a critical factor controlling the size of prepared nanoparticles. Octyltrimethylammoniumbromide (OTAB) is the most suitable surfactant for microemulsion polymerization of PGMA. The surface area and surface functional groups of PGMA nanoparticles increased owing to the size reduction to nanometer scale. It was possible to cure individual PGMA nanoparticles without coagulation and morphological transformation. Judging from these results, the PGMA nanoparticles can be applied for diverse application fields such as surface modifier, coating materials, compatibilizer for polymer blends, and drug delivery agent. |
| 저자 | 고성록, 배준원, 장정식 |
| 소속 | 서울대 |
| 키워드 | Poly (glycidyl meethacrylate); nanoparticle; epoxy resin |
