• Elastomers and Composites
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• v.50 no.3
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• pp.210-216
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• 2015

Polyurethane modified silicone (PUMS) was synthesized from various molecular weights of polydimethylsiloxane (PDMS 2000, PDMS 6000, PDMS 20000), polypropyleneglycol with molecular weight of 3000 g/mol (PPG 3000) and 2,4-toluenediisocyanate (TDI) under tin catalyst. Their structures were confirmed by the measurement of FT-IR and $^1H-NMR$, and the thermal properties were studied from DSC and TGA. Glass transition temperature of PUMS exhibited exothermic peak at $-63{\sim}-69^{\circ}C$, and residual weight was 19~35% at $800^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.16 no.3
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• pp.101-105
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• 1986

The changes of water absorption and surface area of polydimethylsiloxane-5-fluorouracil devices containing different water soluble additives such as sodium chloride, glycerine, poly-propylene glycol(PPG 400), and polyethylene oxide(PEO 400, 400 and 2000) were investigated. It was confirmed that carriers controlled water absorption and swelling of the devices in the aqueous solutions. The water absorption and the swelling were affected by the osmotic pressure and ionic strength of the aqueous solutions.

• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.191-194
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• 2006

• Polymer(Korea)
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• v.31 no.1
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• pp.86-91
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• 2007

Polydimethylsiloxane branched HEMA (SH) was Prepared by reacting polydimethylsilorane prepolymer and 2-hydroxyethyl methacrylate (HEMA). Polyacrylate modified Polyorganosiloxane (SMPA) was prepared by polymerization of methacrylic acid(MA), allyl glycidyl ether(AGE), aminopro- pyltrimethoxysilane (APTS), and SH. Their structures were confirmed by the measurement of FTIR and $^1H-NMR$ and thermal properties of SMPA were studied from TGA. Residual weight of SMPA at $400^{\circ}C$ increased according to increasing content of the APTS to 63 from 55%. SMPA sealant was prepared by adding additives, such as viscosity increasing agent, crosslinking agent, and fillers. Adhesion characteristics of SMPA-3 sealant was determined to be maximum load elongation, 2.01 %, and break load elongation, 2.28%. Adhesion characteristics for SMPA sealant prepared from SMPA-3 were better than those for SMPA sealant prepared from SMPA-1 and SMPA-2.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.140-146
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• 1990

Polydimethylsiloxane(PDMS) containing [N, N'-bis (3- (salicylidene amino) propyl) amine Co(II)] (Co(saldpt)) as a fixed oxygen carrier was synthesized. UV-visible spectra of the membrane demonstrated that Co(saldpt) binded molecular oxygen specificaaly and reversibly. From time lag method experiment, it was found that both oxygen permeability and diffusibity increase with decreasing upstream pressure, while solubility maintain nearly constant. The maximum oxygen permeability and oxygen selectivity over nitrogen obtained was 18.6 barrer and 4, respectively, at 25 mmHg and $40^{\circ}C$ from the the PDMS membrane containing 1 wt% of Co(saldpt). Facilitation behavior was explained in terms of the dual sorption model.

• Journal of the Korean Society of Food Culture
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• v.18 no.1
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• pp.69-74
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• 2003

This study was conducted to find the appropriate fiber for extraction of volatile compounds from Perilla frutescens var. acuta. by solid phase microextraction (SPME). Two SPME fiber, carboxen/polydimethylsiloxane (CAR/PDMS) and polydimethylsiloxane (PDMS) were used to determine the selectivity of the fibers to the different flavor compounds present in the Perilla frutescens var. acuta. Thirty-nine compounds were identified in the volatile compounds extracted by CAR/PDMS fiber, including 6 aldehyde, 1 alcohol, 10 hydrocarbons, 17 terpene hydrocarbons, 2 ketones and 3 benzenes. In PDMS fiber, 3 aldehydes, 2 alcohols, 13 terpene hydrocarbons and 2 miscellaneouses were identified. Perillaldehyde was found to be major volatile flavor component of fresh Perilla frutescens var. acuta. Perillaldehyde and terpene hydrocarbons were more identified in PDMS fiber. These results suggested that the selectivity of PDMS fiber was better than that of CAR/PDMS fiber in Perilla frutescens var. acuta..

• Journal of Adhesion and Interface
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• v.11 no.2
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• pp.70-75
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• 2010

It described the modification of polydimethylsiloxane (PDMS) with amphiphilic methyl methacrylate-based polyethylene glycol (PMMA-b-PEG) to enhance the hydrophilicity of a PDMS surface and cytotoxicity of it. PMMA-b-PEG solutions in water/ethanol mixture was spun-cast on the PDMS surface and the surface was characterized by long-term measurement of water contact angle. The morphology of PDMS surfaces coated with PMMA-b-PEG was characterized by field emission scanning electron microscopy and atomic force microscope. Cytotoxicity of the modified surfaces was investigated by MTT assay which would be necessary for the evaluation of tissue compatibility after implantation of the materials. Based on the MTT assay, PDMS coated with PMMA-b-PEG didn't show any significant cytotoxcity.

• Polymer(Korea)
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• v.32 no.3
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• pp.239-245
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• 2008

Block copolymers of the general formula $[(-CO-R'-CO-HN-Ar-NH-CO-R'-CO)_xNH(CH_2)_3-(Me_2SiO)_y(CH_2)_3NH_2]_n$, [n=18.00 to 1175.0] where $R'=CH_2CH(CH_2GeCl_3)$;$CH_2CHGeCl_3CH_2$; and $Ar=-C_6H_4$;$-(o.CH_3C_6H_4)_2$;$-o.CH_3OC_6H_4)_2$;$-(o.CH_3C_6H_4)$ were prepared by a polycondensation reaction of polyamide containing a pendant trichlorogermyl group and terminal acid chloride $Cl(-CO-R'-CO-NH-Ar-NH-CO-R'-CO-)_xCl$ with aminopropyl-terminated polydimethylsiloxane $H_2N(CH_2)_3(Me_2SiO)_y-(CH_2)_3NH_2]$, (PDMS). These polymers were characterized by elemental analysis, $T_g$, FT-IR, $^1H$-NMR, solid state $^{13}C$-NMR, and molecular weight determination. The thermal stability of these copolymers was examined using thermal analysis techniques, such as TGA and DSC. Their molecular weights as determined by laser light scattering technique ranged $5.13{\times}10^5$ to $331{\times}10^5\;g/mol$. These polymers display their $T_g$ in the range of 337 to $393^{\circ}C$ with an average decomposition temperature at $582^{\circ}C$.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.5
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• pp.321-327
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• 2022

In this paper, a wrinkled structure was formed on the PDMS surface through UV/Ozone treatment, and the wrinkle structure formation mechanism was revealed through physicochemical characterization. A wrinkle structure was formed on the PDMS surface through UV/Ozone treatment for 30 min, and periodic wrinkle formation on the PDMS surface was confirmed by cross-sectional imaging of the scanning electron microscope. In addition, through x-ray photoelectron spectroscopy spectral analysis, it was confirmed that the silica-like-surface of SiOx on the PDMS surface was formed by UV/Ozone. The results of this study not only improve the understanding of the mechanism of wrinkle structure formation on the PDMS surface by UV/Ozone treatment, but also can be used as a basic study to adjust the amplitude and period of the wrinkle structure according to UV/Ozone irradiation conditions in the future.contact angles and the surface energies of FSAMs, it was confirmed that pretilt angles of LC molecules increased according to the alkyl chain length. High optical transparency and uniform homeotropic LC alignment characteristics of FSAMs showed the possibility of FSAMs as an LC alignment layers.

• Clean Technology
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• v.12 no.2
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• pp.62-66
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• 2006

Poly($\small{L}$-Lactide)(PLLA) was prepared by a ring-opening polymerization of $\small{L}$-Lactide with various polydimethylsiloxane(PDMS) based copolymers as a stabilizer in supercritical carbon dioxide($scCO_2$). The block copolymeric stabilizers were synthesized by group transfer polymerization (GTP) by using PDMS macroinitiator. PLLA was found to be produced with fairly low molecular weight distribution as confirmed by gel permeation chromatography(GPC) analysis. Scanning electron microscopy (SEM) results showed that sub-micron size Poly($\small{L}$-lactide)(PLLA) particles were formed by suspension polymerization.