Abstract:
실시예는 광학 재료용 폴리티올 조성물 및 이의 제조방법에 관한 것으로, 실시예에 따른 폴리티올 조성물의 제조방법에 의하면, 폴리티올 화합물 제조시 부반응을 억제하여 부산물인 3관능 폴리티올의 함량이 적고 순도가 높은 4관능 폴리티올 조성물을 얻을 수 있다. 따라서, 순도가 높은 4관능 폴리티올 조성물로부터 얻은 중합성 조성물 및 광학재료는 굴절률, 내열성 등의 광학 특성이 우수하므로, 안경렌즈, 카메라 렌즈 등 각종 플라스틱 광학 재료의 제조에 유용하게 사용될 수 있다.
Abstract:
La présente invention concerne des compositions de solvants comprenant majoritairement au moins un oxyde de sulfure organique, et plus particulièrement le diméthylsulfoxyde, par addition audit oxyde de sulfure organique, d'au moins un agent masquant d'odeur comprenant au moins un composé choisi parmi les mono-esters, les di- ou tri-ester, les alcools, les cétones, les aldéhydes et les terpènes.
Abstract:
This invention relates to a stabilizing composition for S-substituted aldehydes with general formula (I) having 4-15 carbon atoms, where: R1 = C1-C5 alkyl, C6-C9 aryl, furfuryl, benzyl; R2 = H, R1; R3 = H, R1, characterized by the fact that it is based on a prototropic agent (A) in association with an 02 abstracting agent (B). The components are selected among: (A) aromatic or heterocyclic aromatic amines, such as pyridine, dimethylaniline, quinoline, etc., alcanolamines or non-aromatic cyclic amines, such as triethanolamine, N-methylmorpholine, etc., lactams, such as N-methyl pyrrolidone, etc. (B) substituted phenols or hydroquinones, such as p-t-butyl phenol, BHT, etc., acid or unsaturated antioxidant agents, as ascorbic acid or beta-carotene. The amount indicated of said composition is 500-1000 ppm, preferably 1000 ppm, and the (A)/(B) molar ratio is comprised between 5/95 and 50/50. The process for stabilizing S-substituted aldehydes provides for addition to the stabilizing composition to an aldehyde containing up to 300 ppm of water at a stabilization temperature of up to 50 DEG C. The temperature so which the aldehyde is subjected in the stabilization process is 25-100 DEG C, and the aldehydes may be in contact with carbon steel. The proposed (A)/(B) composition is efficient to stabilize aldehyde with a certain amount of H20 in the presence of carbon steel and at a 25-100 DEG C temperature.
Abstract:
The present invention relates to a method of carrying out an organic reaction in aqueous solution in the presence of a hydroxyalkyl(alkyl)cellulose or an alkylcellulose.
Abstract:
본 발명은 3-메르캅토프로피온산의 제조방법과 이를 이용한 메르캅토기를 갖는 카르본산에스테르화합물 및 티오우레탄계 광학재료의 제조방법에 관한 것이다. 본 발명에서는, 3-메르캅토프로피온산을 제조하는 과정에서의 공정 개선으로, 수율을 크게 높이면서 동시에 감압증류 시의 온도를 낮추고 시간을 단축시킴으로써 생성물의 파괴를 막고 생산성을 크게 향상시킬 수 있다. 본 발명은 전체적으로 수행이 어렵지 않은 용이하고 간단한 공정으로 수율과 생산성을 크게 높일 수 있고 최종 수득되는 3-메르캅토프로피온산의 순도 및 색상 또한 우수하므로, 이를 이용하여 저렴한 비용으로 순도 높고 색상이 좋은 메르캅토기를 갖는 카르본산에스테르 화합물을 얻을 수 있고, 이 카르본산에스테르 화합물을 이용하여 역시 저렴한 비용으로 티오우레탄계 중합성 조성물과 이를 중합시킨 티오우레탄계 광학재료를 얻을 수 있다. 본 발명에 따라 얻어지는 카르본산에스테르 화합물은, 특히 저가의 티오우레탄 광학렌즈의 제조에 사용될 수 있으며, 그 결과 저렴하면서도 색상이 좋은 광학렌즈를 얻을 수 있다.
Abstract:
Offenbart wird ein Gemisch enthaltend 86 bis 97 Gew% 2-Hydroxy-4-methylthiobuttersäurenitril, 2 bis 14 Gew% Wasser, 0,05 bis 0,5 Gew% HCN und aufweisend einen pH-Wert von 1 bis 4, gemessen mit einer pH-Elektrode bei 23°C sowie eine Verfahren zur Herstellung eines solchen Gemisches und seine Verwendung als lagerstabile Form von 2-Hydroxy-4-(methylthio)buttersäurenitril.
Abstract:
The invention relates to the manufacture of certain polyunsaturated compounds employing a particular application of the Mitsonobu reaction in the presence of at least one anti-oxidant. We have found a method of making a pharmaceutically-acccptable polyunsaturated ester or thioester compound directly, which can ultimately be converted to the advantageous ketone compounds, in which unwanted oxidation and cis/trans isomerization are substantially reduced or eliminated using particular Mitsonobu chemistry.
Abstract:
La dégradation d'une solution absorbante comportant des composés organiques munis d'une fonction aminé en solution aqueuse est sensiblement réduite en présence d'une faible quantité d'agents inhibiteurs de dégradation soufrés définis par la formule générale : (I) La solution absorbante est mise en oeuvre pour désacidifier un effluent gazeux.
Abstract:
The invention relates to a process for the preparation of methionine of high bulk density, in which a mixture which comprises a compound which has a foaming action and a compound which influences the crystallization is added to the hydrolysis solution, and to the mixture itself.
Abstract:
Methods for using sulfur-containing compounds comprising short chain aliphatic ester or amide moieties as solvents and compositions comprising these compounds are provided.