• 전기화학회지
• /
• 제3권3호
• /
• pp.169-172
• /
• 2000

Polyacrylonitrile (PAN) 고분자의 유기용매 함유능을 증대시키기 위하여 PAN을 수정한 새로운 polyacrylonitrile-co-bis[2-(2-methoxyethoxy)ethyl]itaconate (PANI로 약칭) 공중합체를 합성하였다. PAN과 PANI의 혼합 고분자에 ethylene carbonate (EC)와 dimethyl carbonate (DMC)의 혼합유기용매, $LiClO_4$ 염을 혼합한 젤 고분자 전해질을 제조하였다. 상온에서의 이온전도도는 25PAN +10PANl +50EC/DMC+$15LiClO_4$ 조성의 전해질에서 $2\times10^{-3}\; Scm^{-1}$로 가장 높은 값을 나타내었다. 이는 PANI의 혼합으로 인하여 유기용매 영역의 결정질 성분이 줄어들고, 따라서 전하운반자의 수가 증가하기 때문인 것으로 분석하였다. PANI를 고분자 기질로 적당량 첨가하면, PAN만을 단용으로 사용한 젤-전해질에 비해 기계적 강도가 감소하는 단점이 있기는 하지만, 이온전도성, 열적 특성, 용매와의 혼화성, 전기화학적 안정성, 리튬 전극과의 계면 안정성 등 거의 모든 면에서 성능이 개선되는 것으로 나타났다.

• Biomolecules & Therapeutics
• /
• 제1권2호
• /
• pp.137-142
• /
• 1993

The possible tumor-promoting activities of sodium chloride (NaCl) and dimethyl itaconate (DMI), one of the quinone reductase inducers, were examined on stomach of male Wistar rats treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Administrations of NaCl and DMI after the initiation by MNNG resulted in various sized masses in the rat forestomach. Histopathologic studies showed that the combination of NaCl and DMI made an enhancing effect on the MNNG-induced carcinogenesis, resulting in papilloma in 5 weeks and squamous cell carcinoma in 20 weeks in submucosal area of forestomach. We also used an in vivo shortterm method for evaluating possible tumor-promoting activity with ornithine decarboxylase (ODC) as a marker. The markable inductions of the ODC activities by MNNG, NaCl, and DMI were found in the pyloric mucosa of rat stomach in time-dependent manners. A single administration of MNNG induced ODC activity up to 288 pmol $CO_2$/hr/mg protein at 24 hr after the administration. NaCl caused induction of ODC with a maximum of 179 pmol $CO_2$/hr/mg protein at 8 hr after the administration. ODC was induced up to 539 pmol $CO_2$/hr/mg protein at 16 hr after the administration of DMI. Additional treatment of NaCl and NaCl plus DMl caused 2 fold and 7 fold increases, respectively, in the ODC activity of the MNNG-alone group at 24 hr after the administration. These results suggest that NaCl and DMI have promoting activities in the rat gastric carcinogenesis initiated by MNNG.

• Macromolecular Research
• /
• 제13권2호
• /
• pp.128-134
• /
• 2005

The phosphorus comonomer [(6-oxido-6H-dibenz<1,2>oxaphosphorin-6-yl)methyl]-methyl butane-dioate (DOP-MBDA) was synthesized through the addition reaction of dimethyl itaconate (DMI) with 9,10-dihydro­9-oxa-10-phosphaphenan threne-10-oxide (DOP). A series of novel flame retardant poly(butylene terephthalate)s (PBTs) containing different amounts of phosphorus were prepared using DOP-MBDA as a comonomer. These novel polymers were characterized by $^{1}H-NMR$, IR, and differential scanning calorimetry (DSC). The novel phosphorus­containing poly(butylene terephthalate)s, referred to as FR-PBTs, exhibited interesting thermal and mechanical behavior, as well as superior flame retardancy. These properties are attributed to the effect of incorporating the rigid structure of DOP-MBDA and the pendant phosphorus group into the poly(butylene terephthalate) (PBT) homopolymer. The UL 94-V2 rating could be achieved with this novel flame retardant PBT, which has a phosphorus content as low as $0.5 wt\%$, and the FR-PBTs emitted less fumes and toxic gases than the PBT homopolymer.

• Macromolecular Research
• /
• 제11권5호
• /
• pp.322-327
• /
• 2003

Two kinds of mutually cross-linkable copolymers were prepared to be used as humidity-sensing materials. The humidity-sensitive thin films consist of cross-linked polyelectrolytes of the following component: 4-vinylbenzyl dimethyl 2-(dimethylphosphino)ethyl phosphonium chloride (1)/ bis(2-methoxyethyl)itaconate (2)= 3/l, 2/l, 1/1 and 1/2 and 4-vinylbenzyl chloride (3)/ vinylbenzyl tributyl phosphonium chloride (4)= 3/l, 2/l, 1/1 and 1/2. The humidity sensor prepared from the reaction of 1/2= 2/l with 3/4= 2/l showed an average resistance of 723,36.2 and 2.42 ㏀ at 30, 60 and 90%RH, respectively. Temperature dependence, frequency dependence, and response time were measured and the reliability test such as water durability and long-term stability were also estimated.