Rational Control of Polymer Molecular Weight and Dispersity during Enzyme-Catalyzed Polyester Synthesis in Supercritical Fluids
摘要:
Enzyme-catalyzed polyester synthesis has been investigated with special emphasis on modulation of polymer molecular weight and dispersity. Supercritical fluids were also used for isolating low-disperity polyester fractions by changing pressure. Enzymatic synthesis of low-dispersity polyesters was achieved in supercritical fluoroform. The synthesized polymer molecular weight can be controlled by changing the pressure.
Process for the production of polyesters using enzymes and supercritical fluids
申请人:Bayer Corporation
公开号:EP0729993A1
公开(公告)日:1996-09-04
A process of preparing a polyester by reacting a diol with an acid or acid ester in the presence of a solid enzyme and in a supercritical fluid is described.
描述了一种在固体酶存在下和超临界流体中通过二元醇与酸或酸酯反应制备聚酯的工艺。
POLYESTER BASED DEGRADABLE MATERIALS AND IMPLANTABLE BIOMEDICAL ARTICLES FORMED THEREFROM
申请人:Ashby Valerie
公开号:US20090221781A1
公开(公告)日:2009-09-03
A method of making an aliphatic polyester prepolymer, comprising: reacting, alone or in combination with other reactants, a diol with at least a first diacid (or a diester of said first diacid) to produce an aliphatic polyester prepolymer. The first diacid is preferably a trans-beta-hydromuconic acid (HMA). In some embodiments, the diol contains at least one ether linkage. In some embodiments the diol is further reacted with at a second diacid, or a diester of said second diacid, wherein said second diacid is different from said first diacid. Prepolymers produced from such processes and articles formed therefrom are also described.
Polyester Based Degradable Materials and Implantable Biomedical Articles Formed Therefrom
申请人:Ashby Valerie
公开号:US20120027719A1
公开(公告)日:2012-02-02
A method of making an aliphatic polyester prepolymer, comprising: reacting, alone or in combination with other reactants, a diol with at least a first diacid (or a diester of said first diacid) to produce an aliphatic polyester prepolymer. The first diacid is preferably a trans-beta-hydromuconic acid (HMA). In some embodiments, the diol contains at least one ether linkage. In some embodiments the diol is further reacted with at a second diacid, or a diester of said second diacid, wherein said second diacid is different from said first diacid. Prepolymers produced from such processes and articles formed therefrom are also described.
USE OF LONG CHAIN AMINES AND DIFUNCTIONAL COMPOUNDS AS TRACERS
申请人:Baker Hughes Incorporated
公开号:US20150377010A1
公开(公告)日:2015-12-31
Non-halogenated molecules including, but are not necessarily limited, to alkyl and aromatic amines having from 8 to 18 carbon atoms and salts of these amines, diols having the formula HO—(CH
2
)
n
—OH, diamines having the formula H
2
N—(CH
2
)
n
—NH
2
, dicarboxylic acids having the formula HO.CO—(CH
2
)
n
—CO.OH, diesters having the formula R′O.CO—(CH
2
)
n
—CO.OR″, where n is 4 to 18, and R′ and R″ are independently straight or branched alkyl or aromatic groups of 1-20 carbon atoms, and combinations thereof are used as tracers to measure oil and/or water fluid returns, e.g. from a hydraulic fracturing job. The non-halogenated molecules may be combined with substrates and introduced into a subterranean location, desorbed and recovered from the subterranean location with a fluid, reacted with a reagent to give a derivatized tracer. The presence of the derivatized tracer is then detected in the recovered fluid. Different non-halogenated tracers may be used for each hydraulic fracturing stage.