JPH10310702A - Hydrophilic polymer composition and production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hydrophilic polymer composition excellent in stretchability, low-hardness, mechanical strength, water absorption and adhesivity, and little in elution into water. SOLUTION: This hydrophilic polymer composition is obtained by compounding 100 pts.wt. of a thermoplastic elastomer with 200-1000 pts.wt. of a crosslinked-type water-absorbing polymer, a hydrophilic composition obtained by crosslinking 1-600 pts.wt. of a hydrophilic polymer or oligomer three dimensionally and 100-2000 pts.wt. of a thickener, dehydrating the resultant mixture by preheating, adding 100-1000 pts.wt. of a mineral oil-based softener, and heating this mixture under stirring in an inert gas atmosphere to perform dissolving and mixing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrophilic polymer composition having excellent hydrophilicity, tackiness and low hardness, and more particularly to a water-stopping agent, a cooling agent, various sealants and a packing agent having a high water absorption. The present invention relates to a hydrophilic polymer composition suitably used for a dressing agent for protecting a wound, a building material for preventing dew condensation, and the like, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, in the field of polymer elastomers, functions and performance have been required to be improved along with the expansion of applications, and hydrophilicity having low hardness, high strength, and excellent hydrophilicity and adhesiveness has been demanded. Polymer compositions are required (JP-A-4-76064, JP-A-5-2307).
No. 47, JP-A-6-340705).

As an example, as a polymer composition preferably used for an adhesive tape or the like, there is a polymer composition in which a large amount of a softening agent or a plasticizer is blended with a high molecular organic material in order to achieve low hardness. However, when such a large amount of a softening agent or a plasticizer is blended, it becomes difficult to uniformly knead the mixture using a mixer or the like, and furthermore, the mechanical strength is greatly reduced and the mechanical strength is significantly reduced, and such a material is not practically used. There's a problem.

Further, in order to improve water absorption and tackiness,
Simply adding a water-absorbing polymer or pressure-sensitive adhesive does not provide satisfactory mechanical strength, water-absorbing function, and adhesive strength, and is effective when applied to, for example, water-absorbing agents with high water absorption and anti-condensation agents. In fact, no high polymer composition has been obtained.

Furthermore, compounding agents such as a water-absorbing polymer and a hydrophilic oligomer or a hydrophilic polymer which act as a surfactant have a large dissolution rate in water, so that there is a problem that the water-absorbing ratio decreases with the lapse of use. Yes,
In addition, there is a possibility that it may dissolve into surrounding water or the like and pollute the environment, which has been a serious problem in practical use.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is capable of uniformly dispersing a softening agent, a water-absorbing polymer, and an adhesive in a thermoplastic elastomer. In spite of being soft, it is excellent in mechanical strength, hydrophilicity, especially excellent in water absorption, low dissolution rate in water, and obtaining a polymer composition having high adhesiveness. That is the purpose.

That is, the hydrophilic polymer composition according to the present invention comprises 100 to 1000 parts by weight of a mineral oil-based softener, 200 to 1000 parts by weight of a crosslinked type water-absorbing polymer, and 100 to 100 parts by weight of a thermoplastic elastomer. It is characterized by containing a hydrophilic composition obtained by three-dimensionally crosslinking 1 to 600 parts by weight of a polymer or a hydrophilic oligomer, and 100 to 2,000 parts by weight of a tackifier.

[0008] When the ratio of the softener is less than 100 parts by weight, the fluidity of the elastomer is reduced, so that molding at a low pressure becomes difficult. Is greatly reduced, and the desired physical properties of the elastomer cannot be obtained.

If the ratio of the crosslinked type water-absorbing polymer is less than 200 parts by weight, the desired water-absorbing effect cannot be obtained, and
If the amount is more than 000 parts by weight, the fluidity of the elastomer decreases, and molding at low pressure becomes difficult.

Further, if the ratio of the hydrophilic polymer or hydrophilic oligomer is less than 1 part by weight, there is no effect as a surfactant, and if it is more than 600 parts by weight, characteristics as a soft elastomer are lost.

Here, in the present invention, a hydrophilic composition obtained by three-dimensionally cross-linking the above hydrophilic polymer or hydrophilic oligomer is used so that elution to water is reduced.

When the amount of the tackifier is less than 100 parts by weight, the adhesive strength is sharply reduced, while when the amount is more than 2,000 parts by weight, the desired water absorption cannot be obtained.

Here, preferably, the composition as a whole is
The total mixing ratio of the water-absorbing polymer and the hydrophilic polymer or hydrophilic oligomer is set to about 30 to 50%.

As the thermoplastic elastomer, for example, a styrene elastomer, a vinyl chloride elastomer, an olefin elastomer, a polyester elastomer, a polyamide elastomer, a urethane elastomer, and a mixture of these elastomers are used. Can be.

Examples of the mineral oil-based softener include paraffin-based process oils, naphthene-based process oils, aromatic process oils, polymerized high-boiling strong aromatic oils, paraffin, liquid paraffin, and white oil as petroleum-based softeners. Examples include oil, petrolatum, petroleum sulfonate, Gilsonite, petroleum asphalt, mineral rubber, petroleum resin, coal tar, cumarone and indene resin.

Examples of the water-absorbing polymer include acrylate polymers, carboxylate polymers represented by polyacrylates, starch / acrylate graft copolymer polymers, and sulfonate polymers represented by polysulfonates Etc. are preferably used.

Examples of the hydrophilic polymer or hydrophilic oligomer include cationic surfactants typified by quaternary ammonium salts and anionic surfactants typified by sulfonates, and the addition of polyethylene oxide. Non-ionic surfactants such as phenol, higher alcohols to which polyethylene oxide has been added, polyethylene glycol esters, and polypropylene glycol to which ethylene oxide has been added can also be used. In addition, water-soluble polymers such as polyols such as polyethylene glycol and polytetramethylene glycol, higher alcohols, glycerin, bisphenol A to which ethylene oxide or propylene oxide is added, and polyethylene oxide can also be used.

Examples of the tackifier include a chroman resin typified by chroman indene resin, butylphenol acetylene resin, phenol / formaldehyde resin, terpene / phenol resin, polyterpene resin, xylene / formaldehyde resin, synthetic polyterpene resin, and aromatic carbonized resin. Hydrogen resin, aliphatic hydrocarbon resin, aliphatic cyclic hydrocarbon resin, unsaturated hydrocarbon polymer, isoprene resin, hydrogenated hydrocarbon resin, hydrocarbon tackifying resin, polymerized special polyester, polybutene, Atactic polypropylene, liquid polybutadiene, low molecular weight butyl rubber, pentaerythritol ester of rosin, glycerol ester of rosin, hydrogenated rosin, highly hydrogenated wood rosin, methyl ester of hydrogenated rosin, hydrogenated rosin Triethylene glycol ester, hydrogenated rosin pentaerythritol ester, hydrogenated rosin ester, high melting point ester resin, polymerized rosin, polymerized rosin glycerol ester, zinc resinate, cured rosin, rosin-based tackifier And a mixture of a resin acid and an amine-resin soap, a turpentine tackifier, a co-condensation product of a synthetic resin and a phthalate, and a specially prepared product.

Further, in addition to the above-mentioned compounding materials, for example, DO
Plasticizers of phthalic acid derivatives such as P (dioctyl phthalate), maleic acid derivatives, trimellitic acid derivatives, glycol derivatives, tetrahydrophthalic acid derivatives, azelaic acid derivatives, itaconic acid derivatives, fatty acid derivatives, paraffin derivatives, adipine derivatives, sebacic acid Derivatives, fumaric acid derivatives, citric acid derivatives, oleic acid derivatives, stearic acid derivatives, glycerin derivatives, sulfonic acid derivatives,
A plasticizer such as an epoxy derivative, a phosphoric acid derivative, or a monoester plasticizer may be appropriately added.

The hydrophilic polymer composition of the present invention is produced as follows. First, a cross-linked type water-absorbing polymer, a hydrophilic composition obtained by three-dimensionally cross-linking a hydrophilic oligomer or a hydrophilic polymer, and a tackifier are mixed with a thermoplastic elastomer at a predetermined ratio, and pre-dried to remove moisture. I do. Next, a predetermined amount of a mineral oil-based softener is added, and while stirring with a stirrer such as a temperature-controllable mixer or separable flask, under a predetermined condition of an appropriate temperature and time (for example, 150 to 150 ° C. in an inert gas atmosphere). 200 ° C, 40
Minutes), and then heat-treating the mixture to dissolve and mix the mixture.

[0021]

Industrial Applicability According to the present invention, hydrophilicity is excellent, which is excellent in elasticity, excellent in mechanical strength despite being very soft, and has high water absorption and adhesive strength, and low elution rate to water. A molecular composition can be obtained.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Table 1 shows the formulations of the hydrophilic polymer compositions of Examples 1 to 5 and Comparative Examples 1 and 2 according to the present invention.

[0023]

[Table 1]

A: Styrene-based thermoplastic elastomer B: Mineral oil-based softener C: Cross-linked type water-absorbing polymer D: Hydrophilic polymer or hydrophilic oligomer E: Hydrophilic composition obtained by three-dimensionally cross-linking a hydrophilic polymer or hydrophilic oligomer F: Tackifier (* 1) Kuraray Co., Ltd. (number average molecular weight: about 200,000) (* 2) Matsumura Oil Research Institute Co., Ltd. (* 3) Sanyo Chemical Co., Ltd. (* 4) Sanyo Chemical Co., Ltd. (* 5) Meisei Chemical Co., Ltd. (* 6) Sumitomo Seika Co., Ltd. (* 7) Yashara Chemical Co., Ltd. (* 8) See JIS K6301 (* 9) See JIS K6258 (* 10) Compounding ratio to the total amount of C + D + F (* 11) ( * 9) After the water absorption test, dry in an oven at 100 ° C for 24 hours, measure the weight before the water absorption test and the weight after drying, and dissolve by the following formula It was obtained.

[0025]

(Equation 1)

[Examples 1 to 5] A hydrophilic composition D obtained by three-dimensionally crosslinking a cross-linked type water-absorbing polymer C, a tackifier F, a hydrophilic oligomer or a hydrophilic polymer C with a styrene-based thermoplastic elastomer A is blended. Then, after predrying to remove water, a mineral oil-based softener B was added, and the mixture was stirred using an ACM mixer (manufactured by Aikosha Seisakusho) as a stirrer so that the composition was appropriately dispersed. Then, heat treatment was performed in a nitrogen atmosphere at 200 ° C. for 40 minutes at 217 rpm to obtain each of the hydrophilic polymer compositions of Examples 1 to 5. The mixing ratio of each material is as shown in Table 1.

[Comparative Examples 1 and 2] A crosslinked water-absorbing polymer C, a tackifier F, a hydrophilic oligomer or a hydrophilic polymer C were blended with a styrene-based thermoplastic elastomer A, and a preliminary reaction was performed to remove water. After drying, the mineral oil-based softener B was added, and the mixture was stirred at 200 ° C. in a nitrogen atmosphere using an ACM mixer (manufactured by Aikosha Seisakusho) so as to appropriately disperse the composition. 40 minutes, 2
The heat treatment was performed under the condition of 17 rpm to obtain Comparative Examples 1 and 2.
Was obtained. Table 1 shows the mixing ratio of each material.
As shown in FIG.

Each of Examples 1 to 5 thus obtained
The hydrophilic polymer compositions of Comparative Examples 1 and 2 were subjected to various tests such as hardness, water absorption, tensile strength, elongation, tackiness, and dissolution rate. The results are shown in Table 1.

As apparent from Table 1, all of the hydrophilic polymer compositions of Examples 1 to 5 have a tensile strength of 2 kg / cm ^2.
Above, elongation is 500% or more, water absorption is 100% or more, 2
Adhesion at 5 ° C. is 1000 g / 25 mm or more, and elution rate is less than 4.0%. Although it has high strength, high elasticity, and high water absorption, it has excellent affinity with water. It can be seen that it has excellent characteristics such as high adhesive strength and a small amount of elution into water.

Claims (3)

[Claims] 1. 100 parts by weight of a thermoplastic elastomer, 100 to 1000 parts by weight of a mineral oil-based softener, 200 to 1000 parts by weight of a crosslinked type water-absorbing polymer, 1 to 600 parts by weight of a hydrophilic polymer or a hydrophilic oligomer. Three-dimensionally crosslinked hydrophilic composition, and tackifier 100-2
A hydrophilic polymer composition containing 000 parts by weight. 2. The mineral oil-based softener includes paraffin-based process oil, naphthene-based process oil, aromatic-based process oil, polymerized high-boiling strong aromatic-based oil,
Paraffin, liquid paraffin, white oil, petrolatum, petroleum sulfonate, Gilsonite, petroleum asphalt, mineral rubber, petroleum resin, coal tar,
Or, using a coumarone-indene resin, as the water-absorbing polymer, acrylate, carboxylate polymer, sulfonate polymer, or starch
Using an acrylate graft copolymer polymer, as the hydrophilic polymer or hydrophilic oligomer, a cationic surfactant, an anionic surfactant, a nonionic surfactant, a polyol or a higher alcohol,
The hydrophilic polymer composition according to claim 1, wherein glycerin, bisphenol A to which ethylene oxide or propylene oxide is added, or polyethylene oxide is used. 3. A thermoplastic elastomer, a hydrophilic composition obtained by three-dimensionally cross-linking a cross-linkable water-absorbing polymer, a hydrophilic polymer or a hydrophilic oligomer, and a tackifier are blended, and pre-dried to remove water. A method for producing a hydrophilic polymer composition, comprising adding a mineral oil-based softening agent, heat-treating while stirring in an inert gas atmosphere, and dissolving and mixing.