Abstract:
Provided is an optical glass fiber coating composition which when coated on an optical glass fiber and suitably cured provides a coating having the combination of properties (i) through (iv): (i) a stable tensile modulus that is low at room temperature and over a broad range of temperatures below room temperature, (ii) an adhesion to the optical glass fiber sufficient to prevent structural defects and microbending in the optical glass fiber, (iii) the capability of being removed by stripping from the optical glass fiber substantially no residue left on the optical glass fiber, and (iv) which satisfies each of the following inequalities (I) and (II), X (I), X/Y >/= 1/10 (II), wherein X is the tensile modulus (kg/mm ) measured at 23 DEG C and Y is the tensile modulus (kg/mm ) measured at -40 DEG C. This coating composition comprises: (A) a urethane (meth)acrylate formed from, (a) a diol compound containing at least one structure represented by one of the formulae (1): -CH2-CH20- and (2), (b) a compound containing two isocyanate groups, and (c) a compound containing a (meth)acrylate group and a hydroxy group; (B) a second (meth)acrylate-containing compound of which the homopolymer has a glass transition temperature of at most about 0 DEG C; and (C) a polymerization initiator.
Abstract translation:提供了一种光学玻璃纤维涂料组合物,其在光学玻璃纤维上涂覆并适当固化时提供了具有性能(i)至(iv)的组合的涂层:(i)在室温和过高时稳定的拉伸模量 宽范围的温度低于室温,(ii)对光学玻璃纤维的粘附足以防止光学玻璃纤维中的结构缺陷和微弯曲,(iii)通过从光学玻璃纤维剥离而被除去的能力基本上不含残留物 留在光学玻璃纤维上,和(iv)满足以下不等式(I)和(II)中的每一个,X <= 0.2kg / mm 2(I),X / Y> / = 1/10 (II),其中X是在23℃下测量的拉伸模量(kg / mm 2),Y是在-40℃下测得的拉伸模量(kg / mm 2)。该涂料组合物包含: A)由(a)含有至少一种由式(1)之一表示的结构的二醇化合物形成的氨基甲酸酯(甲基)丙烯酸酯, :-CH 2 -CH 2 O-和(2),(b)含有两个异氰酸酯基的化合物,和(c)含有(甲基)丙烯酸酯基和羟基的化合物; (B)第二(甲基)丙烯酸酯化合物,其均聚物的玻璃化转变温度为至多约0℃; 和(C)聚合引发剂。
Abstract:
The invention relates to a process for the oxidation of toluene in a liquid phase using an oxygen containing gas at a temperature between 120-200 DEG C and a pressure between 2-50 atm in the presence of a catalyst comprising cobalt or manganese as a metal ion further comprising bromide, wherein the amount of metal ion is between 0.2 and 5 wt % with respect to the reaction mixture; the molar ratio of bromide: metal ion is between 0.05 and 4; and whereby the reaction mixture further comprises an organic onium compound in a molar ratio with respect to the metal ion of 0.1 to 4, which compound is able to solubilize the metal ion-bromide complex, whereby the oxidation is carried out in such a way that at least 15 wt % of the converted toluene is benzaldehyde by limitation of the conversion of toluene, whereafter the reaction mixture is subjected to a separation step to separate toluene and benzaldehyde, the toluene being recycled to the reaction mixture.
Abstract:
The invention relates to a process for preparing an aldehyde starting from an unsaturated compound by means of hydroformylation in the presence of hydrogen, carbon monoxide, platinum and a bidentate ligand, the hydroformylation being effected in an aqueous medium and the bidentate ligand being a water-soluble compound. The invention also relates to a process for preparing an aldehyde, in which the following steps are carried out: a) preparation of the aldehyde in a reaction zone using a process as described above, b) isolation of the aldehyde from the aqueous mixture leaving the reaction zone by extraction, c) recycle of the aqueous mixture of step b) to the reaction zone.
Abstract:
Process for the preparation of a threo-phenylserine amide of general formula (2) in which glycine amide is contacted with the corresponding substituted benzaldehyde of formula (3) in an excess relative to the amount of glycine amide, this taking place at a pH between 9 and 14 in the presence of a suitable solvent. The resulting phenylserine amide can subsequently be hydrolyzed to a phenylserine amide of general formula (1), which is subsequently hydrolyzed to a phenylserine amide of general formula (1), which is subsequently subjected to a stereoselective enzymatic hydrolysis yielding a (2S,3R)-phenylserine. The non-hydrolyzed (2R,3S)-phenylserine amide can be isolated as a Schiff base and be recirculated and simply racemized. The (2S,3R)-phenylserine obtained can be used in the preparation of thiamphenicol or phlorophenicol. The threo-phenylserine amides of general formula (1) or (2) are new intermediates in this commercially attractive process for the preparation of thiamphenicol and phlorophenicol.
Abstract:
The invention relates to a process for the preparation of optically active N-substituted-3-pyrrolidinol of general formula (1), wherein R represents a linear, cyclic or branched alkyl, alkenyl, aryl, alkaryl or aralkyl group, optionally substituted with one or more halogen atoms, or wherein R = OR , wherein R may have the same meaning as stated above for R, via enantioselective enzymatic hydrolysis of a corresponding N-substituted-3-acyloxypyrrolidine of general formula (2), wherein R represents an acid residue, for instance a linear, cyclic or branched alkyl, alkenyl, aryl-aralkyl or aralkyl group, optionally substituted with one or more halogen atoms and for the preparation of an optically active N-substituted-3-acyloxypyrrolidine compound, wherein a mixture of the corresponding N-substituted-3-pyrrolidinol is subjected to an enzymatic enantioselective esterification by means of an enzyme with ester hydrolase activity.
Abstract:
Process for the preparation of a beta -lactam derivative, wherein in an enzymatic reaction a beta -lactam nucleus is coupled to D-phenylglycine amide, and the enzyme, the solid phenylglycine and the beta -lactam derivative are separated out, wherein the mixture obtained after the enzymatic reaction, from which mixture at least the enzyme and the solid D-phenylglycine have been removed, is treated with a suitable aldehyde at a pH between 7.5 and 8.5, whereby the Schiff base of D-phenylglycine amide is formed, and the Schiff base of D-phenylglycine amide is separated out. The treatment with a suitable aldehyde preferably takes place before the beta -lactam derivative is separated out.
Abstract:
A copolymer having an RSV less than 0.6 and a process for its preparation in which ethylene, at least one other 1-alkene and, optionally, an aliphatic or alicyclic polyunsaturated monomer are polymerized in the presence of a catalyst system containing (1) a compound of vanadium, (2) at least one organometal compound, (3) an alpha -halo, ketoaromatic promoter and (4) a chain transfer agent in which the molar ratio of alkyl groups of the alkyl aluminum halide to halogen atoms is at least 1.5.
Abstract:
The invention relates to a catalyst that is suitable for the preparation, via a Ziegler polymerisation, of an olefine polymer, comprising an organometallic compound and a transition metal-imidoaryl complex, characterised in that the complex contains at least one amido group bound to the transition metal, the aryl group in the complex being an o,o-disubstituted phenyl group.
Abstract:
The invention relates to a powder paint comprising a free carboxylic acid groups-containing polymer as a binder and a beta -hydroxyalkylamide groups-containing compound as a crosslinker. The free carboxylic acid groups-containing polymer is a polymer having an average functionality of less than 2. The polymer is preferably a polyester or a polyacrylate.
Abstract:
The invention relates to a powder paint based on acrylics. The thermosetting powder paint comprises a hydroxyl functional acrylic resin and an isocyanate crosslinking agent blocked with a blocking agent wherein the isocyanate crosslinking agent is an adduct of an isocyanate and a mixture of polyetramethylene ether glycol and at least one additional, but other glycol, selected from the group consisting of glycols and polyglycols.