摘要:
A method of production is provided which is capable of efficiently producing in a very short period of time a porous polymer possessing a uniform foam structure and truly excelling in absorption properties and physical properties. It is a method for the production of a porous polymer, characterized by comprising (a) an emulsifying step for forming a water-in-oil type high internal phase emulsion (HIPE) by mixing and stirring an oil phase containing a polymerizing monomer component and a surfactant as essential components, (b) a shaping step for shaping the HIPE in a specific form, and (c) a polymerizing step for polymerizing the shaped HIPE and controlling the temperatures of the emulsion at the component steps (a)-(c) so that they may not produce a change exceeding 10° C. or controlling all the component steps so that they may proceed at temperatures of not lower than 80° C.
摘要:
An object of this invention is to provide a method for the production of a porous cross-linked polymer, which permits the polymerization (curing) of a water in oil type high internal phase emulsion (HIPE) in such an exceptionally brief time as not more than 30 minutes, preferably not more than 10 minutes without impairing the stability of the HIPE. The object of this invention mentioned above can be accomplished by a method for the production of a porous cross-linked polymer which comprises steps of mixing an oil phase containing a polymerizing monomer, a cross-linking monomer, and a surfactant as essential components with a water phase containing water as an essential component thereby obtaining a water in oil type high internal phase emulsion and heating said emulsion to a prescribed curing temperature thereby polymerizing the emulsion, wherein said emulsion is formed in a thickness of not more than 50 mm and the temperature-increasing rate of the emulsion is not less than 5° C./minute.
摘要:
This invention concerns a method for the production of a porous polymer from a water-in-oil type high internal phase emulsion (HIPE). By using an oil-soluble polymerization initiator as the polymerization initiator, the method for producing a porous polymer with outstanding characteristics in a very short period even when the porous polymer is produced from an HIPE exhibiting a viscosity of not more than 500 mPa second at the emulsion formation temperature or when the porous polymer to be produced possesses a number-average pore diameter of not less than 80 &mgr;m is provided.
摘要:
A method for producing a porous material excelling in stability of preservation is produced. A method for the production of a porous material comprising a step for obtaining a porous polymer by polymerizing an HIPE containing a polymerizable monomer is disclosed, which method comprises a step for adding a compound capable of reacting with a polymerization initiator and/or a compound capable of reacting with an unsaturated double bond to said emulsion, said porous polymer and/or said porous material having a conversion of not less than 70%. According to this invention, it is made possible to produce a porous material excelling in stability in storage and to decrease the polymerization initiator and the residual monomer very simply.
摘要:
This invention is targeted at providing a method for producing a porous cross-linked polymer material excelling in absorption properties and mechanical strength in a short period of time. In the production of a porous cross-linked polymer material from an HIPE, the method of this invention is characterized by comprising a step of polymerizing the HIPE till the bromine value thereof falls to not more than 25% of the value existing prior to the polymerization and a subsequent step of after curing the porous cross-linked polymer material by means of an active energy ray or a temperature higher than the polymerization temperature.
摘要:
A hydrogel polymer obtained by polymerizing a monomer component including acrylic acid (salt) is post-neutralized so that each of polymer particles derived from a polymer produced by neutralizing the hydrogel polymer has an allowable neutralization ratio. The polymer as obtained by neutralizing the hydrogel polymer is reacted with a crosslinking agent reactive to a functional group of the polymer. The allowable neutralization ratio, for example, is a neutralization ratio which is not lower, by not less than 20 mole percent, or more than, at least 55 mole percent, than an average neutralization ratio of a mass of the polymer particles, and the post-neutralization is carried out so that a number of polymer particles having a non-allowable neutralization ratio outside the allowable neutralization range is not more than 10 in 200 polymer particles, thus obtaining a water-absorbent agent having high absorbency under no applied pressure and high pressure wherein the amount of water soluble component is lower compared with the conventional water-absorbent agent and a change in pH of a swollen gel is small.
摘要:
An object of this invention is to provide a method for the production of a porous material by polymerizing a water-in-oil type high internal phase emulsion in a briefer time than a conventional technique without impairing the stability of the emulsion. The object of this invention can be accomplished by a method for the production of a porous material comprising a step of polymerizing a water-in-oil type high internal phase emulsion containing a polymerization initiator, wherein the polymerization initiator is a redox type initiator combining an oil-soluble oxidizing agent and a reducing agent, either of the oil-soluble oxidizing agent or the reducing agent is preparatorily added to form the emulsion, and thereafter the remainder of the reducing agent or the oil-soluble oxidizing agent is added to the emulsion to polymerize the added emulsion.
摘要:
An object of this invention is to provide a method for the production of a porous material by polymerizing a water-in-oil type high internal phase emulsion in a briefer time than a conventional technique without impairing the stability of the emulsion. The object of this invention can be accomplished by a method for the production of a porous material comprising a step of polymerizing a water-in-oil type high internal phase emulsion containing a polymerization initiator, wherein the polymerization initiator is a redox type initiator combining a water-soluble oxidizing agent and a reducing agent, the reducing agent is preparatorily added to form the emulsion, and thereafter the water-soluble oxidizing agent is added to the emulsion to polymerize the added emulsion.
摘要:
The particulate water absorbent has a cross-linking structure therein, and contains (i) a particulate water absorbent resin having a cross-linking structure on a surface therof and (ii) not less than 0.001 mass % and less than 10 mass % of anorganic acid multivalent metal salt whose molecule contains not less than seven carbon atoms. Futher, the particulate water absorbent contains 90 mass % of particles, whose particle diameter is not less than 106 μm and 850 μm, with respect to the particulate water absorbent.
摘要:
The particulate water absorbent has a cross-linking structure therein, and contains (i) a particulate water absorbent resin having a cross-linking structure on a surface therof and (ii) not less than 0.001 mass % and less than 10 mass % of anorganic acid multivalent metal salt whose molecule contains not less than seven carbon atoms. Futher, the particulate water absorbent contains 90 mass % of particles, whose particle diameter is not less than 106 μm and 850 μm, with respect to the particulate water absorbent.