JP4653438B2 - Emulsion composition for latent heat storage material - Google Patents

Description

  The present invention uses the latent heat of fusion at the time of phase change using cheaper nighttime energy during off-peak hours of power demand in order to solve the shortage of power supply due to the dramatic increase in the use of air conditioning with changes in living environment. This is related to the application technology of the cold storage system. More specifically, the present invention relates to an emulsion composition for a latent heat storage material mainly composed of n-paraffin which is a linear saturated hydrocarbon, water and a surfactant.

In recent years, the use of air conditioning in office buildings and homes has been increasing, but in preparation for the peak of power demand in the summer, the development of heat storage materials that accumulate cold energy for air conditioning using nighttime power has become active. . Electricity cannot be stored, and power generation facilities must be constructed to meet peak demand. Therefore, if the gap between maximum demand and minimum demand is large, efficient operation of power generation facilities is difficult, leading to an increase in supply costs. It was.
The heat storage that promotes the effective use of electric power has a load leveling effect that corrects the bias of the electric power consumption (load) depending on the time zone, and it also serves as an opportunity to suppress excessive investment in electric power equipment.
As this latent heat storage material, a composition composed of n-paraffin or the like and water utilizing an endothermic or exothermic phenomenon accompanying a phase change of a hydrocarbon compound has been widely attempted.

Such heat storage materials include those in which a heat storage material such as a hydrocarbon compound is encapsulated in a microcapsule, but this method is not economically preferable because the capsule strength is weak and easily deteriorated and the cost is high. There is.
On the other hand, as an economically advantageous method, there is a method of emulsifying a heat storage material with a surfactant. It is considered that the emulsion composition for a latent heat storage material obtained by this method can increase the amount of heat transported per unit flow rate of the fluid latent heat material transport. As an advantage, (1) the effect of promoting heat transfer (2) Reduction of pipe diameter, (3) Reduction of pump power, and (4) Reduction of pressure loss accompanying flow.

Under such circumstances, a large number of emulsion compositions for latent heat storage materials have been proposed in Patent Literature 1 to Patent Literature 9 below. These proposals are basically methods for obtaining an oil-in-water type latent heat storage material emulsion composition using a hydrocarbon-based compound represented by n-paraffin as a heat storage material and using a surfactant. However, in any of these cases, there is room for improvement in heat storage performance, emulsion stability, durability, viscosity, etc., and the current situation is that the requirements of the market are not satisfied.
JP 57-40582 A Japanese Patent Laid-Open No. 7-126614 Japanese Patent Laid-Open No. 9-255944 JP 2000-336350 A JP 2003-321684 A Japanese Patent Laid-Open No. 9-13022 JP 2004-2833 A JP 2004-143229 A JP 2004-161794 A

  An object of the present invention is to provide a durable emulsion composition for a latent heat storage material that exhibits excellent emulsifying dispersibility and emulsification stability, has low viscosity, and has a large endotherm and heat generation accompanying phase change.

As a result of carrying out intensive research to solve the above problems, the present inventors have demonstrated excellent emulsification dispersibility and emulsification stability by using a specific surfactant, have low viscosity, and endotherm accompanying phase change. The inventors have found that a durable emulsion composition for a latent heat storage material having a large calorific value can be obtained, and have reached the present invention.
That is, the present invention is an emulsion composition for a latent heat storage material mainly composed of n-paraffin, water and a surfactant, and the surfactant comprises (A) 5 to 50% by weight of a polybutenyl succinate. (B) It is a mixture with 95-50 weight% of polyoxyalkylene alkyl ether phosphates, It is an emulsion composition for latent heat storage materials characterized by the above-mentioned.

As a preferred embodiment of the present invention, the (A) polybutenyl succinate has an average molecular weight of 300 to 3000, and is composed of ammonia, an organic amine, a monovalent alkali metal hydroxide, and a monovalent alkali metal salt. There is an emulsion composition for a latent heat storage material which is a salt partially or completely neutralized by one or more selected.

（但し式中、Ｒ_１は炭素数６〜２２の直鎖もしくは分岐鎖のアルキル基又はアルケニル基、又は炭素数８〜１８のアルキル基を有するアルキルフェニル基を示し、（ＡＯ）_ｘはＡがエチレン基及び／又はプロピレン基から成る（ポリ）アルキレンオキサイド基を示す。ｘは０〜３０、ｙは１又は２、ｚはｙ＋ｚ＝３の関係を満たす整数を示す。Ｍは水素原子もしくは１価の金属原子、アンモニア、有機アミンを示す。）で表される潜熱蓄熱材用エマルション組成物がある。 In another preferred embodiment of the present invention, the polyoxyalkylene alkyl ether phosphate (B) is represented by the following general formula (B):

(In the formula, R ₁ represents a linear or branched alkyl group or alkenyl group having 6 to 22 carbon atoms, or an alkylphenyl group having an alkyl group having 8 to 18 carbon atoms, and (AO) _x represents A A (poly) alkylene oxide group composed of an ethylene group and / or a propylene group, x is 0 to 30, y is 1 or 2, z is an integer satisfying the relationship y + z = 3, M is a hydrogen atom or monovalent. In this case, the emulsion composition for a latent heat storage material is represented by the following formula:

Thus, by using the surfactant according to the present invention, that is, polybutenyl succinate and polyoxyalkylene alkyl ether phosphate at a constant blending ratio, excellent emulsification dispersibility and emulsion stability are exhibited. A durable latent heat storage material emulsion composition having a low viscosity and a large endothermic and exothermic heat accompanying phase change can be obtained.
Although the reason why the emulsion composition for latent heat storage materials having excellent performance can be obtained by using the surfactant mixture of the present invention has not yet been elucidated, it is an emulsified and dispersed substance. The polybutenyl group of the polybutenyl succinate according to the present invention and the alkyl group of the polyoxyalkylene alkyl ether phosphate according to the present invention effectively act on the surface of a hydrocarbon compound such as n-paraffin. And a synergistic effect due to the combined use of two surfactants according to the present invention.
The polybutenyl succinate and the polyoxyalkylene alkyl ether phosphate of the present invention are not effective even when used alone, and the performance is remarkably lowered even when the blending ratio limited in the present invention is deviated.

Hereinafter, the present invention will be described in detail.
The (A) polybutenyl succinate according to the present invention can be easily obtained by a known production method. For example, polybutene or liquid polybutene can be hydrolyzed by reacting maleic anhydride and then partially or completely neutralized with alkalis. In these, in order to acquire the effect of this invention, it is preferable that the average molecular weights of polybutenyl succinate are 300-3000, and it is more preferable that it is an average molecular weight 800-2000.
Further, in order to obtain the polybutenyl succinate of the present invention, the alkalis used for neutralization include monovalent alkali metal hydroxides such as caustic soda and caustic potash, ammonia, monoethanolamine, diethanolamine, triethanolamine and the like. Alkanolamines, morpholine, cyclohexylamine, monopropanolamine and other organic amines can be mentioned, but alkanolamines are preferred from the viewpoint of effects.

  The polyoxyalkylene alkyl ether phosphate represented by the general formula (B) according to the present invention can be obtained by a known production method. For example, octyl alcohol, 2-ethylhexyl alcohol, decyl alcohol, dodecyl alcohol (lauryl alcohol), tridecyl alcohol, tetradecyl alcohol, (myristyl alcohol), pentadecyl alcohol, hexadecyl alcohol (palmityl alcohol), octadecyl alcohol (stearyl alcohol) ), Higher alcohols such as octadecenyl alcohol (oleyl alcohol), or alkylphenols such as phenol, nonylphenol, dodecylphenol, dinonylphenol, etc., using phosphoric anhydride, or octyl alcohol, 2-ethylhexyl alcohol, Decyl alcohol, dodecyl alcohol (lauryl alcohol), tridecyl alcohol, tetradecyl alcohol (Myristyl alcohol), pentadecyl alcohol, hexadecyl alcohol (palmityl alcohol), octadecyl alcohol (stearyl alcohol), higher alcohols such as octadecenyl alcohol (oleyl alcohol), or phenol, nonylphenol, dodecylphenol, dinonylphenol, etc. An alkylene oxide such as ethylene oxide or propylene oxide is added to the alkylphenol of the above by a known method, phosphorylated with anhydrous phosphoric acid, and then monovalent alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, Alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine, morpholine, cyclohexylamine, monopropanolamine, etc. It can be obtained by neutralization with machine amine.

  Further, as the polyoxyalkylene alkyl ether phosphate of the present invention, 1 mol of phosphoric anhydride is added to 2 to 3 mol of a compound obtained by adding 1 to 30 mol of higher alcohol or alkylphenol or ethylene oxide and / or propylene oxide thereto. A polyoxyalkylene alkyl ether phosphoric acid reacted is preferably obtained by reacting with the alkali to form a neutralized salt in view of the effect. Among these, after reacting 1 mol of phosphoric acid with 2.7 mol of a compound obtained by adding 3 to 10 mol of ethylene oxide and 0 to 5 mol of propylene oxide to 1 mol of oleyl alcohol or tridecyl alcohol in terms of effects. Most preferred are polyoxyalkylene alkyl ether phosphates neutralized with monoethanolamine or morpholine.

The ratio of the surfactant mixture used in the present invention is preferably within the range of (A) 5 to 50% by weight of polybutenyl succinate and (B) 95 to 50% by weight of polyoxyalkylene alkyl ether phosphate. However, if the blending ratio is out of this range, it is not preferable because it is equal to or less than the case of single use in terms of emulsion stability, which is the effect of the present invention.
In addition, the surfactant mixture of the present invention is preferably used in an amount of 0.5 to 10.0% by weight based on the total weight of n-paraffin and water. It is in the range of 7.0% by weight.
If the amount used is less than 0.5% by weight, the stability of the emulsion for a latent heat storage material of the present invention cannot be obtained. On the other hand, if the amount used exceeds 10.0% by weight, the phase change and the heat storage efficiency will be hindered. Also, it is not preferable.

  The n-paraffin according to the present invention is a general term for linear aliphatic hydrocarbons, and generally available ones can be used. Specifically, n-decane, n-undecane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-eicosane, n-docosan, etc. Among them, those having 10 to 20 carbon atoms are preferable, those having 14 to 18 carbon atoms are more preferable, and those having 15 to 16 carbon atoms are particularly preferable.

Various addition adjuvants can be further blended in the emulsion composition for a latent heat storage material of the present invention. Examples of specific compounds include higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ethylene oxide adducts, fatty acid amide ethylene oxide oils and fats as nonionic surfactants. Examples include adducts, polypropylene glycol ethylene oxide adducts, glycerol alcohol fatty acid esters, fatty acid esters of pentaerythritol, fatty acid esters of sorbitol and sorbitan, fatty acid esters of sucrose, alkyl ethers of polyhydric alcohols, and fatty acid amides of alkanolamines. Anionic surfactants include soaps, higher alcohol sulfates, higher alkyl ether sulfates, sulfated oils, sulfated fatty acid esters, sulfated olefins, alkylbenzene sulfonates, alkylnaphthalene sulfonates, paraffin sulfonates, etc. Examples of cationic surfactants include alkyltrimethylammonium salts, alkyldimethylbenzylammonium salts, and cationized cellulose, and examples of amphoteric surfactants include alkylbetaines, alkylamidobetaine imidazolines, and glycines.

In addition, the emulsion for latent heat storage materials according to the present invention has a heat storage material in a fine particle state (average particle diameter of 0.05 to 1.0 μm) to eliminate supercooling and to easily solidify, thus sufficiently storing heat. Therefore, it is preferable to add a certain amount of nucleating agent.
Examples of the nucleating agent include medium / high temperature synthetic waxes and natural waxes. For example, FNP-0080, FNP-0085, FNP-0090, FNP-0100, FNP-0105, FT- manufactured by Nippon Seiwa Co., Ltd. 100, FNP-0115, and the like, and other animal / plant waxes, mineral waxes, petroleum waxes, compounded waxes obtained by processing these, and oxidized waxes. Among these, preferred waxes are synthetic waxes such as FNP-0085. , FNP-0090 and the like.
These nucleating agents are preferably used in an amount of 0.1 to 10.0% by weight based on the total weight of n-paraffin and water. When the amount is less than 0.1% by weight, the latent heat amount of the emulsion for latent heat storage material is insufficient, and when it exceeds 10.0% by weight, the stability of the emulsion is deteriorated and the desired effect of the present invention is not exhibited. In view of the effect, the more preferable amount used is in the range of 1.0 to 5.0% by weight.

The emulsion for latent heat storage materials of the present invention can be prepared by a known method. For example, a so-called phase inversion emulsification method in which hot water is added little by little to a mixture of n-paraffin and a nucleating agent heated and melted in advance, and a mechanical emulsification method using a homomixer, dispal mill, high-pressure emulsifier, etc. As long as an oil-in-water emulsion is obtained, the production method is not particularly limited.
A preferable production method is to obtain the emulsion by the phase inversion emulsification method, and then perform the above-described mechanical emulsification. The emulsion thus produced is stable without being separated or demulsified even if the solidification and dissolution are repeated 90 times for 3 months. An emulsion is obtained.

The emulsion composition for a latent heat storage material according to the present invention includes a partially saponified and fully saponified polymer compound such as polyvinyl alcohol, an antiseptic, a rust inhibitor, Antibacterial agents, corrosion inhibitors, chelating agents and the like are added, but the addition amount and addition method are not particularly limited.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to a following example, unless the meaning is exceeded.

Compound production example 1
<Production example of polybutenyl succinate according to the present invention>
A reaction vessel was charged with 1000 g (1.0 mol) of Nisseki polybutene (manufactured by Nippon Oil Corporation, average molecular weight 1000) and 118 g (1.2 mol) of maleic anhydride, and the temperature was raised to 70 to 80 ° C. after nitrogen substitution. Dissolve mixed for 1 minute. Subsequently, the temperature is raised to 230 to 240 ° C., and after the reaction for 6 hours, the mixture is cooled to 90 ° C. Next, 22 g (1.2 mol) of water was added, and the mixture was hydrolyzed by stirring at 100 ° C. for 3 hours. After cooling to 40 ° C., 71 g (1.2 mol) of monoethanolamine was gradually added, and polybutenyl (average) according to the present invention was added. Molecular weight 1000) 1200 g of monoethanolamine salt of succinic acid (A-1) was obtained.
In the same manner as for compound A-1, compounds A-2 and A-3 shown in Table 1 and compound C-1 other than the present invention were synthesized.

Compound production example 2
<Synthesis of Polyoxyalkylene Alkyl Ether Phosphate (B-1 to 6) According to the Present Invention> Synthesis of B-1 compound: 270 g of oleyl alcohol and 0.5 g of caustic potash as a catalyst are added to an autoclave, and 264 g of ethylene oxide is added thereto. Was reacted at 170 to 180 ° C. over 3 hours, and then 57 g of phosphoric anhydride was added at 35 to 55 ° C., followed by reaction at 100 ° C. for 3 hours.
Thereafter, the mixture was cooled to 30 ° C., and 45 g of monoethanolamine was added in small portions to partially neutralize, and the compound according to the present invention having a pale yellow viscous oil having a pH of 5.1, 630 g of polyoxyethylene oleyl ether phosphate monoethanolamine salt (B-1) Got.
In the same manner as for compound B-1, compounds B-2 and B-5 shown in Table 1 and compounds C-2 and C-3 other than the present invention were synthesized.
Synthesis of B-3 compound: To an autoclave, 280 g of oleyl alcohol and 0.7 g of caustic potash as a catalyst were added, and a mixture of 176 g of ethylene oxide and 116 g of propylene oxide was randomly reacted at 160 to 170 ° C. over 3 hours, and then After adding 57 g of phosphoric anhydride at 35 to 55 ° C., the mixture was reacted at 100 ° C. for 3 hours.
Thereafter, the mixture was cooled to 30 ° C. and 35 g of morpholine was added in small portions to partially neutralize to obtain 650 g of a light yellow viscous oily polyoxyethylene polyoxypropylene oleyl ether phosphate morpholine salt (B-3) having a pH of 5.2.
In the same manner as for compound B-3, compounds B-4 and B-6 shown in Table 1 and compound C-4 other than the present invention were synthesized.

Compound Example <Production Method of Mixture 1>
In a mixing vessel, 50 parts by weight of polybutenyl (average molecular weight 1000) succinic acid monoethanolamine salt (Compound A-1) and 50 parts by weight of polyoxyethylene (4 mol) oleyl ether phosphoric acid monoethanolamine salt (Compound B-1) were charged. The mixture 1 was obtained by mixing at 30 to 40 ° C. for 30 minutes.
Moreover, the mixtures 2-13 of this invention and the comparative mixtures 1-6 were obtained by the same method. Table 2 summarizes the blend compositions of Mixtures 1-13 and Comparative Mixtures 1-6.

<Preparation of emulsion 1>
540 parts by weight of water is added to a 2 L emulsification container and heated to 80 ° C. In another 1 L container, 230 parts by weight of n-pentadecane (C ₁₅ ) and n-hexadecane (C ₁₆ ) and synthetic wax FNP-0085 (Japan) 30 parts by weight of Seiwa Co., Ltd., melting point 85 ° C.) and 20 parts by weight of an emulsifier composition (mixture 1 of the present invention) are added and mixed, and dissolved by heating at 80 ° C. This was added and emulsified in warm water for 5 minutes while stirring at 7000 rpm with a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Subsequently, the mixture was stirred for 5 minutes, and then emulsified for 1 pass at a pressure of 300 kg / cm ² using a high pressure emulsifier (manufactured by Nippon Seiki Co., Ltd.) at 60 to 70 ° C., and then cooled to 20 to 35 ° C. to obtain an emulsion 1. . In the same manner, the emulsions 2 to 9 and 13 of the present invention (each using the mixtures 2 to 9 and 13 of the present invention shown in Table 2) and the comparative emulsions 1 to 3 and 5 (each shown in Table 2). Comparative mixtures 1 to 3 and 5) were obtained.

<Preparation of emulsion 2>
Add 500 parts by weight of water to a 2 L emulsification container and heat to 60 ° C. In another 1 L container, 200 parts by weight of n-pentadecane, 300 parts by weight of n-hexadecane and 60 parts by weight of an emulsifier composition (mixture 10 of the present invention) Are mixed and warmed to 80 ° C. The mixture was gradually added to water with emulsification and emulsified, and then stirred with a TK homomixer (manufactured by Tokushu Kika Co., Ltd.) for 5 minutes at 7000 rpm and cooled to 20-30 to obtain an emulsion 10.
Emulsions 11 and 12 of the present invention (using the inventive mixtures 11 and 12 shown in Table 2, respectively) and comparative emulsions 4 and 6 (using the comparative mixtures 4 and 6 shown in Table 2 respectively) are obtained in the same manner. It was.
Table 3 summarizes the formulations of Examples 1 to 13 and Comparative Examples 1 to 6 for producing the emulsion.

<Evaluation of emulsion>
Using the emulsifier composition prepared according to the formulation shown in Table 2, an emulsion for a heat storage material based on the formulation of Table 3 was prepared. These emulsions were measured for (1) differential scanning calorimetry (DSC), (2) temperature cycle test, (3) viscosity, (4) flash point, and the like. The evaluation results are shown in Table 4.
Test Method (1) DSC (Thermal Analyzer DSC6200 manufactured by Seiko Instruments Inc.)
Temperature control (electric cooler) 20 → 0 → 20 (0 ° C 15 minutes hold, cooling and heating rate 1 ° C / min)
Heat storage amount (mj / mg) = heat of fusion (2) Temperature cycle test Add 4L of emulsion to a 5L glass bottle and immerse it in a low-temperature thermostatic water bath and set the flow rate of the magnet pump (manufactured by Sansei Electric Co., Ltd.) to 8L / min. As Hr), circulation was repeated alternately at a temperature of 10 ° C. (12 hours in the day) and 25 ° C. (12 hours at night), and the emulsion stability, viscosity, and DSC were measured after 15 days and 45 days.
(3) Viscosity BM viscometer 5 ° C
In the examples, the rotor No. 1. Measured at 60 rpm. In the comparative example, the rotor No. 2 was used and measured at a rotation speed of 12 rpm.

Test result No. in Table 4 1 to 13 are emulsions in Examples of the present invention, and Comparative Example No. 1 to 6 are the results of testing emulsions other than the present invention.
The heat storage material emulsion composition of the present invention does not cause phase separation even in a long-term cycle test as shown in Table 4, and can be used stably for a long time. Furthermore, since it has a low viscosity and sufficient fluidity, it can be applied to various air conditioners and the like. Moreover, the test results in the DSC measurement are also good, and the heat storage efficiency is about twice that of the emulsion using the comparative compound, so that it can be remarkably used as a material constituting a heat storage system for the purpose of labor saving and efficiency of air conditioning energy and environmental protection. An excellent heat storage material can be provided.

By using the emulsifier composition of the present invention, it is possible to provide an emulsion composition for a latent heat storage material that is excellent in viscosity and emulsion stability, has no problem of supercooling, and has high heat storage efficiency. In particular, it is easy to transport by piping and is optimal for use as a heat storage material used in heat transfer systems.

Claims (3)

An emulsion composition for a latent heat storage material mainly comprising n-paraffin, water and a surfactant, wherein the surfactant comprises (A) 5 to 50% by weight of polybutenyl succinate, and (B) An emulsion composition for a latent heat storage material, which is a mixture of 95 to 50% by weight of a polyoxyalkylene alkyl ether phosphate. The (A) polybutenyl succinate has an average molecular weight of 300 to 3000, and one or more selected from ammonia, organic amine, monovalent alkali metal hydroxide, and monovalent alkali metal salt The emulsion composition for a latent heat storage material according to claim 1, wherein the emulsion composition is a salt partially or completely neutralized by. The (B) polyoxyalkylene alkyl ether phosphate is represented by the following general formula (B)

(In the formula, R ₁ represents a linear or branched alkyl group or alkenyl group having 6 to 22 carbon atoms, or an alkylphenyl group having an alkyl group having 8 to 18 carbon atoms, and (AO) _x represents A A (poly) alkylene oxide group composed of an ethylene group and / or a propylene group, x is 0 to 30, y is 1 or 2, z is an integer satisfying the relationship y + z = 3, M is a hydrogen atom or monovalent. The emulsion composition for a latent heat storage material according to claim 1 or 2 represented by: