Korea Research Institute of Chemical Technology

Jong Geon Jegal

Bong Keun Song

Dong Yeop Oh

Sung Yeon Hwang

Seung Hwan Lee

In-Chul Kim

Kyung Sik Hong

In Yong Eom

Chan Duck Jung

Ju Hyun Yu

Jeyoung Park

Tae Ho Kim

Ju Young Lee

Sun-Chang Kim

Hyeon Yeol Jeon

Seohyun Kim

In Seung Jang

Jung Hoon Kim

Kew Ho Lee

Je Young Park

Jae Chang Lee

Suk Chea Jung

Seon Mi Kim

Myung Suk Shin

Si Gyeong Lee

Hyun Gil Cha

Seul A Park

Ho Jun Kim

A method for preparing an aramid nanofiber dispersion includes dissolving an aromatic polyamide-based polymer in a solution including a basic material and an aprotic polar solvent, while performing stirring so that a nanofiber is produced, wherein the aromatic polyamide-based polymer is a polymer in a form of a solid which is not spun into a fiber form, the stirring is performed at a temperature of 50° C. or lower and at a speed of 10-1000 rpm so that a time taken for the aromatic polyamide-based polymer to be dissolved and formed into an aramid nano-fiber dispersion is 80 hours or less, an aramid nanofiber in the aramid nanofiber dispersion has an average diameter of 1 to 100 nm and an average length of 0.1 to 100 μm, and the basic material includes potassium hydroxide or sodium hydroxide.

Method for preparing aramid nanofiber dispersion

A biodegradable composite material which is produced by polymerizing a mixture of an aqueous dispersion of a natural polymer nanofiber including any one or more of a chitin nanofiber and a cellulose nanofiber, a dicarboxylic acid or a derivative thereof, and a diol. The biodegradable composite material has excellent biodegradable and mechanical properties.

Biodegradable composite material having improved mechanical properties using natural polymer nanofiber aqueous dispersion and method of producing the same

A polybutylene succinate (PBS) nanocomposite material includes a matrix comprising polybutylene succinate chains, and nanocelluloses dispersed between the polybutylene succinate chains. The PBS composite material may be produced by polymerizing 1,4-butanediol and succinic acid or a derivative thereof in a mixture of 1,4-butanediol and succinic acid or a derivative thereof with nanocelluloses. The PBS nanocomposite material and the method have improved properties, which does not require a surface hydrophobization pretreatment process of cellulose, melt kneading, and solution mixing processes.

PBS composite material and method for producing same

A self-restoring polyurethane-based polymer obtained by polymerization of a composition containing an aromatic disulfide diol represented by Chemical Formula, HO&#x2014;Ar&#x2014;S&#x2014;S&#x2014;Ar&#x2014;OH, an alicyclic polyisocyanate, and a polyol. Arand Areach are independently a substituted or unsubstituted C-Carylene group. The composition satisfies Equation, 0.1&#x2264;M/M. Mis a total mole number of the aromatic disulfide diol in the composition, and Mis a total mole number of the aromatic disulfide diol and the polyol in the composition.

Self-restoring polyurethane-based polymer and preparation method therefor

Provided are a recombinant yeast having improved ability to produce ginsenoside, which is prepared by overexpressing INO2 and INO4 or deleting OPT1 in a yeast having ability to produce ginsenoside, a method of preparing the yeast, and a method of producing ginsenoside by using the yeast.

Increased production of ginsenosides through yeast cell organelle improvement

The present invention relates to recombinant yeast, in which the productivity of ginsenoside is enhanced by overexpressing CPR5, PDI1, or ERO1 in yeast having the productivity of ginsenosides; a method for preparing the yeast; and a method for producing ginsenosides using the yeast.

Increased production of ginsenosides through improvement of protein-folding machinery of yeast

The present invention relates to a method for preparing bioethanol from lignocellulosic biomass. The method of the present invention is capable of: minimizing the impurity content of an enzymatic saccharification raw material, by extracting biomass using hot water, before pretreatment, and removing extractable substances such as inorganic salts; suppressing, to the greatest extent, the production of overdecomposition products of sugar, by pretreating the biomass, from which the hot water extractable substances have been removed, in a condition for maximizing xylan yield; preparing fermentable sugar at a low cost, without washing a pretreated solid obtained from subsequent solid-liquid separation, but by only concentrating a sugar solution obtained after enzymatic saccharification, using a separation film; and preparing bioethanol therefrom in high yield.

Method for preparing sugar, bioethanol or microbial metabolite from lignocellulosic biomass

The present invention relates to a method for preparing, from wood-based biomass, a high concentration of fermentable sugar which can be effectively used in culturing various industrial fermented bacteria. According to the method of the present invention, biomass can be extracted by hot water prior to a pre-treatment so as to remove extractible substances such as mineral salts to thus minimize the content of impurities in raw materials for an enzymatic saccharification. The biomass from which substances extractible by hot water are removed is pre-treated in the condition where xylan yield rate is maximized, thus achieving maximum inhibition of the generation of over-decomposed products of sugar. Subsequently, fermentable sugar for culturing various industrial fermented bacteria can be prepared in an inexpensive manner by only concentrating, using a separator membrane, the sugar solution obtained by an enzymatic saccharification of the pre-treated solid content obtained by a solid-liquid separation without washing the solid content with water.

Method for preparing fermentable sugar from wood-based biomass

The present invention relates to a method for preparing a stereoblock polylactide, comprising: a step of obtaining a first reaction mixture with a monomer conversion rate of 80 to 95% by adding a catalyst to a D-lactide and growing a PDLA chain; a step of obtaining a second reaction mixture with a monomer conversion rate of 80 to 95% by adding an L-lactide to the first reaction mixture and growing a racemic PDLLA chain at the end of the PDLA chain; and a step of further adding an L-lactide to the second reaction mixture and growing a PLLA chain at the end of the PDLLA chain through a polymerization reaction. The preparation method is capable of providing a more convenient synthesis by skipping a process of removing residual monomers in the middle of the reaction, and also of preventing multi-blocking and oligomerization of polymer chains due to a mixture of chains by gradually adding polymerizable monomers while controlling the monomer conversion rate in a one-port synthesis, thereby reducing chain transfer during the polymerization.

Method for preparing stereoblock polylactide

An ionomer for an ion complex membrane useful for the separation of water-organic solvent by osmosis or low pressure osmosis as well as by pervaporation and a method for producing ion complex membrane therefrom are disclosed. The ionomer for producing ion complex membrane can be prepared by heat polymerization of an alkyl compound having pyridyl groups such as 1,3-di(4-pyridyl) propane at both terminal ends with a dihaloalkane compound such as dibromooctane and dichloroheptane having two halogen atoms at both terminal ends or with one or two halogen atoms affixed to intermediate carbon atoms in a polar solvent such as acrylonitrile. An ion complex membrane can be produced by preparing a membrane of a polycation or polyanion in a solution casting method and dipping the membrane in a solution of polycation or polyanion for 24 hours to give an ion complex membrane. This ion complex membrane may be a single membrane or composite membrane. Composite membrane includes a plain membrane and a hollow fiber membrane. The ion complex membrane according to the present invention is useful for the separation of water-organic solvents.

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Ulsan, South Korea

Jong Geon Jegal