摘要:
A polycarbonate resin obtained by reacting a carbonate raw material with a dihydroxy compound, having: a ratio (Mw/Mn) of a weight-average molecular weight (Mw) to a number-average molecular weight (Mn) of not more than 2.2:1, calculated as polystyrene, when measured by gel permeation chromatography; and a ratio (Mv/Mn′) of a viscosity-average molecular weight (Mv) calculated according to the following formulae, to a number-average molecular weight (Mn′) calculated based on the number of molecular ends, of not more than 1.40:1. &eegr;sp/C=[&eegr;]×(1+0.28&eegr;sp) [&eegr;]=1.23×10−4×(Mv)0.83 wherein &eegr;sp is a specific viscosity of the polycarbonate resin when measured with respect to a methylene chloride solution thereof at 20° C.; and C is a concentration of the methylene chloride solution, in the present case, the methylene chloride solution having a polycarbonate resin concentration of 0.6 g/dl is used. The above polycarbonate resin has a molecular weight distribution close to that of monodisperse system, and generates an extremely less amount of volatile components derived from oligomers, upon heat-molding thereof.
摘要:
There is provided a polycarbonate resin with a reduced volatile chlorine content in which the amount of a chlorinous matter as volatilized from the resin when the resin is heated at 280.degree. C. for 30 minutes and then allowed to stand at room temperature for 3 days is 30 ppb or lower as calculated in terms of the amount of Cl atom. There is also provided a process for producing a polycarbonate resin using phosgene as a raw material, the improvement comprising using phosgene having a chlorine concentration of up to 1,000 ppb as the raw material thereby to provide the resin with a reduced volatile chlorine content.
摘要:
A random copolymerized polyamide resin is prepared by reacting a lactam of the formula (I): ##STR1## wherein R.sup.1 is a C.sub.2-11 alkylene group optionally substituted with a substituent having 1 to 6 carbon atoms, with a hexamethylenediamine-adipic acid salt while concentrating the aqueous solution of the salt to a concentration of at least 70% by weight and while maintaining a uniform reaction phase at all times by controlling the pressure over and the temperature of the reaction medium such that the hexamethylenediamine-adipic acid salt does not precipitate, said pressure being up to not greater than 2 kg/cm.sup.2 .multidot.G and said temperature being up to not greater than 150.degree. C., and then mixing in the solution of the lactam of formula (I) thereby effecting copolymerization and forming a polyamide resin having a relative viscosity measured by the sulfuric acid solution method (1% at 25.degree. C.) of 1.5 to 8.0.
摘要:
The object of the present invention is to provide a polycarbonate resin having an extremely narrow molecular weight distribution, good flowability when melting, and particularly extremely good flowability when melting that does not depend on shear rate. The present invention relates to a polycarbonate resin, characterized in that a value obtained by dividing difference between a logarithmic value log MV9.12 of a melt viscosity (Pa·s) measured at shear rate of 9.12 sec−1 and a logarithmic value log MV1824 of a melt viscosity (Pa·s) measured at shear rate of 1824 sec−, with a capillary rheometer having a die diameter of 1 mmφ and an effective length of 30 mmL, by a viscosity average molecular weight Mv calculated by the following equations, viscosity difference/molecular weight ratio, is 2.0×10−5 or less. ηsp/C=[η]×(1+0.28ηsp) [η]=1.23×10−4×Mv0.83 (In the above equations, ηsp is a specific viscosity measured at 20° C. with respect to a methylene chloride solution of a polycarbonate resin, C is a polycarbonate resin concentration of the methylene chloride solution, and C=0.6 g/dl).
摘要:
Disclosed are a method for producing a polyamide resin which comprises the steps of extracting with water a polyamide resin obtained by polymerizing caprolactam in the presence of water; condensing the extracted aqueous solution containing unreacted caprolactam and its low polymerized materials; and polymerizing the condensate by adding an additional amount of caprolactam, the improvement wherein (a) among the low polymerized materials of caprolactam, a cyclic dimer is supplied to a polymerization reactor after subjecting it to ring-opening reaction to give a chain structure material in an amount of 15% by weight or more based on the total amount of the cyclic dimer, or (a') a condensate obtained by condensing said aqueous solution until reaching a water partial pressure of 10 kg/cm.sup.2 G or more and a temperature of 230.degree. C. or higher is supplied to a polymerization reactor, and then (b) said additional amount of caprolactam is added to the polymerization reactor, and the procedures are repeatedly carried out.
摘要翻译:公开了一种聚酰胺树脂的制造方法,其特征在于,包括以下步骤:在水的存在下,通过聚合己内酰胺得到的聚酰胺树脂; 将提取的含有未反应的己内酰胺及其低聚合物的水溶液冷凝; 并通过加入额外量的己内酰胺使缩合物聚合,其中(a)己内酰胺的低聚合物中的环状二聚体经过开环反应后供入聚合反应器,得到链状结构材料 相对于环状二聚体的总量为15重量%以上的量,或(a')通过将所述水溶液冷凝至达到10kg / cm 2 G以上的水分压和230℃以下的水分 向聚合反应器供给等级(℃)以上,然后向聚合反应器中加入(b)所述附加量的己内酰胺,重复进行。
摘要:
A jointing structure comprising multiple steps provided face to face at the coaxially built traveling path ends with an expansion gap between, multiple elastic members respectively mounted inside the multiple steps, and a joint block mounted on the multiple elastic members across the expansion gap. Multiple supporting blocks and one or more than one intermediate joint block are mounted inside the multiple steps with the joint block between. The multiple supporting blocks, the joint block and the one or more than one intermediate joint block are of concrete. The elastic members are joined together across the expansion gap. The elastic member on one side is fixed to the inside of the step on one side and then subjected to deformation toward the bridge girder axis, and thereafter, the elastic member on the other side is fixed to the inside of the step on the other side.
摘要:
The object of the present invention is to provide a method of producing plural kinds of aromatic polycarbonates by a melt process without changeover loss and quality deterioration. The present invention relates to a production method of an aromatic polycarbonate, comprising supplying a molten mixture of raw materials of an aromatic dihydroxy compound and/or a carbonic diester prepared in the absence of an ester exchange catalyst to polycondensation steps of two lines each equipped with three vertical reactors connected in series and one horizontal reactor, and at the same time, continuously conducting polycondensation reaction in the presence of an ester exchange catalyst.
摘要:
The object of the present invention is to provide a production method of a high molecular weight aromatic polycarbonate containing a reduced amount of a high melting point product, and having less thermal history received and excellent hue by a melt process. The present invention relates to a production method of an aromatic polycarbonate, characterized in that in producing an aromatic polycarbonate using an aromatic dihydroxy compound and a carbonic diester as raw materials and using plural reactors, a molten reactant temperature T1 (° C.) in at least one reactor A and a molten reactant temperature T2 (° C.) in a reactor B subsequent to the reactor A are satisfied with the relationship of T2
摘要:
A subject for the invention is to provide a branched aromatic polycarbonate which is excellent in hue and in melt characteristics such as melt strength.The invention provides a branched aromatic polycarbonate having a viscosity-average molecular weight of 16,000 or higher obtained by the transesterification method, characterized in that the ratio of the weight-average molecular weight (Mw) to number-average molecular weight (Mn) as measured by gel permeation chromatography and calculated for standard polystyrene (Mw/Mn) is in the range of from 2.8 to 4.5 and that the proportion of the number of moles of all structural units yielded by a rearrangement reaction in the course of melt polymerization reaction to 1 mol of structural units having the framework of an aromatic dihydroxy compound used as a starting material is higher than 0.3 mol % and not higher than 0.95 mol.
摘要:
It is an object of the present invention to provide a method for reducing crushing of grain when the grain having Vickers hardness Hv in a range of 11≦Hv≦14 is transported by means of gas. The present invention is a gas transportation method for grain having Vickers hardness Hv in a range of 11≦Hv≦14, and gas transportation is performed under the condition that a velocity V of transportation gas is set at a value in a range of 10 m/s≦V≦20 m/s. Alternatively or additionally, a blending ratio &mgr; expressed as a ratio of a flow amount of the grain (kg/H) to a flow amount of the transportation gas (kg/H) is set at a value in a range of (3 V−30)≦&mgr;≦(3 V−20).
摘要翻译:本发明的目的是提供一种当维氏硬度Hv在11 <= Hv <= 14范围内的颗粒通过气体输送时,可以减少颗粒破碎的方法。 本发明是维氏硬度Hv在11 <= Hv <= 14的范围内的颗粒的气体输送方法,并且在输送气体的速度V被设定在 10m / s <= V <= 20m / s。 或者或另外,以谷物流量(kg / H)与输送气体流量(kg / H)的比率表示的混合比例mu设定为(3V- 30)<= mu <=(3 V-20)。