摘要:
Processes for producing a hydroxyalkyl(meth)acrylate which comprise reacting (meth)acrylic acid with an alkylene oxide in the presence of a catalyst. A first process is characterized in that the amount of the acid ingredient is kept, on calculation, at 0.010 or more in terms of molar ratio to the catalyst present in the liquid reaction mixture and that the liquid reaction mixture from which the hydroxyalkyl(meth)acrylate has been distilled off is used in the subsequent reaction. A second process is characterized in that a dialkylene glycol mono(meth)acylate is supplied to the reaction system to cause the dialkyleneglycol mono(meth)acylate to coexist in the liquid reaction mixture.
摘要:
There is disclosed a novel production process for a hydroxyalkyl (meth)acrylate in which: the diffusion of harmful substances due to disposal of catalysts can be reduced; and also the amount of the catalyst as used can be greatly saved in the entire production process. This production process comprises the step of carrying out a reaction between (meth)acrylic acid and an alkylene oxide in the presence of a catalyst in order to produce the hydroxyalkyl (meth)acrylate; with the production process being characterized by further comprising the step of recovering the catalyst as has been used for the reaction.
摘要:
Processes for producing a hydroxyalkyl(meth)acrylate which comprise reacting (meth)acrylic acid with an alkylene oxide in the presence of a catalyst. A first process is characterized in that the amount of the acid ingredient is kept, on calculation, at 0.010 or more in terms of molar ratio to the catalyst present in the liquid reaction mixture and that the liquid reaction mixture from which the hydroxyalkyl(meth)acrylate has been distilled off is used in the subsequent reaction. A second process is characterized in that a dialkylene glycol mono(meth)acylate is supplied to the reaction system to cause the dialkyleneglycol mono(meth)acylate to coexist in the liquid reaction mixture.
摘要:
The present invention provides: a high-quality hydroxyalkyl (meth)acrylate of which the alkylene glycol di(meth)acrylate content and the acid component content are both low; and its novel production process. The hydroxyalkyl (meth)acrylate, which has a content, in terms of an alkylene glycol di(meth)acrylate as an impurity, of not more than 0.1 weight % and an acid component content of not more than 0.1 weight %, is obtained by a process comprising the step of carrying out a batch reaction between (meth)acrylic acid and an alkylene oxide in the presence of a catalyst in order to produce the hydroxyalkyl (meth)acrylate; with the process making an adjustment as to charging of both raw materials in such a manner that, for, of a time as needed for supplying both raw materials, a supplying time of not less than 40% of a total supplying time when the raw materials as supplied have a temperature of not lower than 40° C., the molar ratio of the integrated amount of the alkylene oxide to the integrated amount of the (meth)acrylic acid that have been added to a reactor by then can be more than 1.0.
摘要:
The present invention provides a novel production process for a hydroxyalkyl (meth)acrylate, in which it is possible that: in a batch reaction system, the amount of the hydroxyalkyl (meth)acrylate (which is the objective product) as produced is kept nearly on the same level as conventional and further, at the same time, there is suppressed the side production of the alkylene oxide's diaddition product (dialkylene glycol mono(meth)acrylate) that lowers the purity of the product to thus give a bad influence upon its quality. The present invention production process comprises the step of carrying out a batch reaction between (meth)acrylic acid and an alkylene oxide in the presence of a catalyst in order to produce the hydroxyalkyl (meth)acrylate; with the production process being characterized by arranging that the reaction should be initiated in a state of a catalyst concentration of more than 1, wherein the catalyst concentration is defined as the amount of the catalyst as used relative to the integrated amount of the (meth)acrylic acid as supplied and is assumed to be 1 in terms of the amount of the entire catalyst to be used relative to the amount of the entire (meth)acrylic acid to be supplied.
摘要:
The present invention provides: a production process for a hydroxyalkyl(meth)acrylate, which can raise productivity together with avoiding danger of explosion, and further can suppress side-formation of impurities such as a diester or a monoester wherein the impurities have a bad influence on product quality. When the time from the start of adding an alkylene oxide (AO) till the end of supplying the entirety of the AO is defined as T (hour), the amount of more than 50% of the entirety of the AO is supplied before T/2 (hour) has passed since the start of adding the AO. In addition, when the total amount of an AO as supplied and the time from the start of adding the AO till the end of supplying the entirety of the AO are defined as W (mol) and T (hour) respectively, the supply of the AO is started at a supplying speed V0 (mol/hour) that is faster than the average supplying speed V (=W/T) (mol/hour), and thereafter the supplying speed of the AO is decreased at least once, and then the supply of the entirety of the AO is completed for T (hour) from the start of adding the AO.
摘要:
The present invention provides a process and its utilization in a process comprising the step of carrying out an addition reaction of an alkylene oxide to an addition-receiving substance in the presence of a resin catalyst, thereby producing the addition reaction product, when the resin catalyst as used for the reaction is persevered so as to recycle it after it is recovered, the unreacted alkylene oxide remaining in the resin catalyst can be prevented from polymerizing and solidifying during the preservation, and the resin catalyst accordingly can be preserved stably for a long time. The resin catalyst as recovered after it is used for the reaction may be preserved under any of the following conditions: 1) at a low temperature of not higher than 40° C.; 2) in the presence of a carboxylic acid; 3) in the presence of a liquid having an alkylene oxide concentration of not more than 2 weight %; and 4) in the coexistence of a carboxylic acid and a liquid having an alkylene oxide concentration of not more than 2 weight %. The present catalyst is recycled for the above addition reaction.
摘要:
It is an object of the present invention to provide a membrane separation apparatus and a membrane separation process that are unlikely to cause membrane fouling and plugging, capable of achieving membrane separation even with relatively low flow rate of water, have an excellent membrane packing density, and are unlikely to cause deposition of foreign components in the apparatus. In order to achieve the above object, according to the present invention, vessel-type inner casings are disposed in a pressure vessel along the longitudinal axis thereof, in which the pressure vessel has a water inlet at a first end and a concentrate outlet at a second end. A flow-regulating plate is disposed on the side of the water inlet of the pressure vessel. Stacks of membrane separation units are respectively disposed in the inner casings, and spacers are disposed between the adjacent membrane separation elements. The spacers also serve as sealing members. Each stack of the membrane separation units and the spacers together define a through-hole extending from a first side to a second side, of the stack of the membrane separation elements. The inner casings have permeate discharge passages along the longitudinal axis thereof. The permeate discharge passages are communicated with the through-hole of each stack of the membrane separation elements. Water that has been fed into the pressure vessel via the flow-regulating plate permeates through the membrane separation elements and is discharged to the outside via the through-holes and the permeate discharge passages.
摘要:
An automatic blood pressure measuring apparatus including an occluding device having a cuff to apply a pressure to a body member of a subject, and a blood-pressure determining device to determine a blood pressure according to a variation in a pulse wave in relation to a change in the cuff pressure. The apparatus comprises a detector for monitoring a blood circulatory system of the subject, and generating signals representing an abnormality associated with the circulatory system. The apparatus further comprises a control device for actuating the occluding device to apply the cuff pressure to the body member, and causing the blood-pressure determining device to execute a predetermined series of blood-pressure measuring steps to measure the blood pressure, thereby permitting an automatic measurement of the blood pressure of the subject when the blood circulatory system is found abnormal by the detector.
摘要:
A computer keyboard which enables a computer to automatically recognize nomenclature information (ID) of keys is provided. Preferably, the keyboard contains a first memory which stores a table in which nomenclature information (ID) of keys and resistance values are associated with each other, a resistor having a resistance value substantially equal to any one of the resistance values, and a controller connected to the first memory and the resistor. The controller detects the resistance value of the resistor and reads the ID of the key corresponding to the resistance value from the table.