WO2021025134A1 - Latent heat storage material composition, and method for controlling latent heat storage characteristics - Google Patents

Abstract

In order to provide a latent heat storage material composition and a latent heat storage characteristic control method capable of controlling latent heat storage characteristics of a phase-change material (PCM) via a rate of reaction to a fatty acid ester produced by an esterification reaction of a fatty acid and an alcohol, or by a transesterification reaction between a feedstock oil-and-fat and an alcohol, the present invention provides a latent heat storage material composition that has a fatty acid ester as a main component, the latent heat storage material composition comprising a fatty acid and a fatty acid ester produced from the fatty acid and an alcohol, and the content of the fatty acid and the content of the fatty acid ester in the composition each being 1 wt% or more.

Description

Latent heat storage material composition and latent heat storage characteristic control method

The present invention relates to a latent heat storage material composition and a method for controlling the latent heat storage characteristics, and the coagulation / melting temperature or transition enthalpy depends on the reaction rate of the esterification reaction or the ester exchange reaction with the latent heat storage material composition formed mainly using a fatty acid ester. The present invention relates to a method for controlling latent heat storage characteristics such as.

As one of the energy-saving technologies, materials and products in which the latent heat storage material is microencapsulated and dispersed are being developed. As such a latent heat storage material, paraffin derived from petroleum was mainly used, but in recent years, it has been proposed to use a fatty acid ester. Fatty acid esters are expected as new latent heat storage materials because they have a wide melting point and high latent heat according to the carbon chain length and the number of double bonds of fatty acids and alcohols.

Patent Document 1 (Japanese Unexamined Patent Publication No. 63-205385) has been proposed as a latent heat storage material using such a fatty acid ester. In this document, latent heat that can take out stable latent heat at a substantially constant temperature in a temperature range of 10 to 20 ° C. without causing a supercooling phenomenon, and can stably store and dissipate heat for a long period of time. As a heat storage material composition, a latent heat storage material composition containing 50 to 100% by weight of n-butyl ester of palmitic acid in a latent heat storage material composition containing fatty acid esters as a main component has been proposed.

Further, Patent Document 2 (WO2011 / 099871) proposes a method for producing a saturated fatty acid ester suitable for use as a phase change material. That is, this document includes a step of hydrogenating a fatty acid ester obtained by processing a triglyceride-containing starting material, and in a preferred embodiment thereof, the fatty acid ester to be hydrogenated is a triglyceride-containing starting material and alcohol. It is obtained by transesterification.

Further, in Non-Patent Document 1 (Binary mixtures of fatty acid acid mice as phase change materials for low temperature applications), a two-component mixture of fatty acid methyl ester as a phase change material for low-temperature use is used as a two-component mixture of fatty acid methyl ester. doing. That is, with respect to incorporating phase change materials into concrete pavement as a means of improving anti-freezing measures, the binary mixture of fatty acid methyl esters provides desirable thermal properties for use as low temperature phase change materials to improve anti-freeze measures. In particular, the binary mixture of methyl laurate and methyl myristate, and methyl laurate and methyl palmitate has eutectic melting temperatures and latent heat of melting of 0.21 ° C and 2.4 ° C, 174.3J, respectively. -It is disclosed that it is g-1 and 166.5 J.g-1.

JP-A-63-205385 WO2011 / 099871

As mentioned above, some techniques for using fatty acid ester as a latent heat storage material or a phase change material (hereinafter referred to as "PCM") have been proposed. However, the conventionally provided PCM composed of fatty acid esters focuses on the selection of fatty acid esters, not the reaction rate in the production of fatty acid esters.

Therefore, the present invention is a latent heat storage material composition capable of controlling the latent heat storage characteristics of PCM by the reaction rate to the fatty acid ester produced by the esterification reaction of fatty acid and alcohol or the transesterification reaction of raw material fat and alcohol. , And to provide a method for controlling latent heat storage characteristics.

In recent years, it has been desired to switch the PCM to a biomass-derived product with high sustainability and safety. Fatty acid esters can be produced from naturally-derived fats and oils, fatty acids and alcohols, and have a wide melting point and high latent heat according to their carbon chain lengths and the number of double bonds, and are therefore expected as biomass-derived PCMs.

Therefore, one of the problems of the present invention is to provide a PCM mainly composed of a fatty acid ester produced by using naturally derived fats and oils, fatty acids and alcohol.

Furthermore, the fatty acid esters used are also expensive because they are industrially manufactured by batch reaction using a phase-matching catalyst using edible refined oil as a raw material, and only methyl esters of several fatty acid groups are sold. The reality is that it has not. As a result, there is also a problem of production efficiency of fatty acid ester used as PCM.

Therefore, in the present invention, a fatty acid ester having a desired melting point / freezing point can be easily produced by a heterogeneous resin catalytic method capable of continuously producing a fatty acid ester by a combination of various fatty acids and alcohols or a combination of various raw material fats and oils and alcohols. Synthesis is also one of the issues.

In order to solve at least one of the above-mentioned problems, the present invention produces a PCM having desired latent heat storage characteristics according to the reaction rate in the esterification reaction of fatty acid and alcohol or the transesterification reaction of raw material fat and alcohol. We have succeeded in what we can do and have completed the present invention.

That is, in the present invention, in order to solve at least one of the above-mentioned problems, a latent heat storage material composition containing fatty acid esters as a main component, the fatty acid, and the fatty acid ester produced from the fatty acid and alcohol. Provided is a latent heat storage material composition comprising 1 wt% or more of each of a fatty acid and a fatty acid ester in the composition.

Further, in the present invention, in relation to the latent heat storage material composition, fatty acid esters are produced with one alcohol and two or more fatty acids, two or more alcohols and one fatty acid, or two or more alcohols and two or more fatty acids. Provided is a latent heat storage material composition which has been used.

Further, in the present invention, in order to solve at least one of the above-mentioned problems, a latent heat storage material composition containing fatty acid esters as a main component, which is a raw material fat and oil, and a fatty acid produced from the raw material fat and oil and alcohol. Provided is a latent heat storage material composition comprising an ester and having a fatty acid ester content of 1 wt% or more and 99 wt% or less in the composition.

In such a latent heat storage material composition, the raw material fat and oil may be one kind and two or more kinds may be combined, and the alcohol used for producing the fatty acid ester is also one kind and two or more kinds may be combined. It can also be used.

The fatty acid used for producing the above fatty acid ester may be a commercially available product, but natural oil can be used as a raw material. For example, ester synthesis using waste oil as a raw material in vegetable oil or the like can be performed, thereby producing a fatty acid ester.

Further, in the present invention, in addition to the latent heat storage material using the latent heat storage material composition according to the present invention, it is a method for controlling the latent heat storage characteristics of other latent heat storage materials, and the latent heat storage material is mainly fatty acid esters. It is composed as a component, and the fatty acid esters are produced by an esterification reaction of fatty acid and alcohol or an ester exchange reaction of fat and oil and alcohol, and the abundance ratio of the fatty acid ester produced in any of the reactions (in other words, For example, a method for controlling the latent heat storage characteristic, which controls the latent heat storage characteristic by the reaction rate of fatty acid or fat or oil), is provided.

The present invention is a method for producing various latent heat storage material compositions containing fatty acid esters as main components in addition to the latent heat storage material composition, wherein a raw material fat or oil or a mixed solution of fatty acid and alcohol is brought into contact with an ion exchanger. Provided is a method for producing a latent heat storage material composition, which comprises continuously producing a fatty acid ester using the ion exchanger as a catalyst. In particular, an anion exchange resin catalyst can be used in the transesterification reaction using raw material fats and oils, and a cation exchange resin catalyst can be used in the transesterification reaction using fatty acids.

The latent heat storage material composition of the present invention is composed of a fatty acid and a fatty acid ester produced from the fatty acid and an alcohol, and the content of the fatty acid and the fatty acid ester is formed to be 1 wt% or more in each of the compositions. Then, a latent heat storage material composition capable of controlling the latent heat storage characteristics by arbitrarily adjusting the fatty acid ester content or the fatty acid content in the composition (that is, adjusting the esterification reaction rate) can be obtained. Can be provided. That is, in the esterification reaction of fatty acid and alcohol, the latent heat storage material composition having arbitrary latent heat storage characteristics can be produced by adjusting the reaction rate with the fatty acid ester to be produced. As a result, in the present invention, a latent heat storage material composition having arbitrary latent heat storage characteristics can be produced by adjusting the progress of the esterification reaction.

Further, in the present invention, a latent heat storage material composition comprising a raw material oil and fat and a fatty acid ester produced from the raw material oil and fat and an alcohol, and the content of the fatty acid ester is 1 wt% or more and 99 wt% or less in the composition. By doing so, naturally-derived oils such as vegetable waste oils can be used as raw material fats and oils. As a result, it is possible to provide a PCM mainly composed of a fatty acid ester produced by using naturally derived fats and oils, a fatty acid and an alcohol, and it is possible to provide a biomass-derived PCM having high sustainability and safety.

Then, in the PCM containing fatty acid esters as the main component, the latent heat storage characteristics of the latent heat storage material are controlled by the reaction rate at the time of production of the fatty acid ester used in the latent heat storage material composition, whereby the fatty acid ester is produced at the time of production. A PCM having desired characteristics can be easily produced only by controlling the reaction rate.

Then, the fatty acid ester used in the latent heat storage material composition of the PCM is brought into contact with a raw material fat or oil or a mixed solution of fatty acid and alcohol in contact with an ion exchanger (that is, an anion exchange resin catalyst and / or a cation exchange resin catalyst). By continuously producing the ion exchanger as a catalyst and controlling the production process so as to obtain a desired reaction rate, a latent heat storage material composition having the desired latent heat storage characteristics can be easily produced. can do. According to the production method, a fatty acid ester having a desired melting point and / or freezing point can be easily synthesized by an heterogeneous resin catalyst method capable of continuously producing a fatty acid ester by combining various fatty acids and alcohols.

Process flow of the conventional method and the method according to the present embodiment DSC melting curve of each binary mixture in Experimental Example 1 Thermophysical properties of each binary mixture in Experimental Example 1 DSC melting curve for fatty acid esters derived from four waste oils in Example 2 DSC melting curve of methyl esterification of cacao butter in Experimental Example 2 Changes in palmitic acid concentration and reaction rate over time in Experimental Example 3 DSC curve of palmitic acid methyl esterification in Experimental Example 3 Composition _T onset in Experiment _{3, T offset,} graph showing the effect on _{T peak} and ΔH Changes in ester concentration and reaction rate in Experimental Example 4 over time DSC curve of esterification with palmitic acid and mixed alcohol in Experimental Example 4 Composition _T onset in Experimental Example _{4, T offset,} graph showing the effect on _{T peak} and ΔH Changes in ester concentration and reaction rate in Experimental Example 5 over time DSC curve of esterification with mixed fatty acid and methanol in Experimental Example 5 Composition _T onset in Experimental Example _{5, T offset,} graph showing the effect on _{T peak} and ΔH DSC curve of esterification with mixed fatty acid and ethanol in Experimental Example 6 Composition _T onset in Experiment _{6, T offset,} graph showing the effect on _{T peak} and ΔH

Hereinafter, the latent heat storage material composition and the latent heat storage characteristic control method according to the present embodiment will be specifically described. In particular, the present embodiment specifically describes a technique for producing a latent heat storage material composition having desired latent heat storage characteristics based on the reaction rate in the fatty acid ester production process.

The latent heat storage material composition according to the present embodiment can be composed of a raw material fat or fatty acid and a fatty acid ester produced by reacting the raw material fat or fatty acid with an alcohol.

The raw material oils and fats include vegetable oils such as soybean oil, rapeseed oil, sunflower oil, cotton oil, peanut oil, sesame oil, palm oil, olive oil and rice bran oil, and animal oils such as beef fat, pork fat, butter, fish oil and whale oil. Waste oil such as deodorized distillate (scum oil) discharged in the deodorizing process during the production of cooking oil can be used.

In addition to saturated fatty acids, unsaturated fatty acids can be used as the fatty acids, and not only linear fatty acids but also branched fatty acids, cyclic fatty acids or aromatic fatty acids, short-chain fatty acids and medium-chain fatty acids can be used. It may be a fatty acid or a long-chain fatty acid. Among these fatty acids, as the saturated fatty acid, for example, acetic acid (C2), capric acid (C8), palmitic acid (C16), stearic acid (C18), and behenic acid (C22) can be used, and unsaturated fatty acids can be used. As, palmitoleic acid (C16: degree of unsaturation 1), oleic acid (C18: degree of unsaturation 1), linoleic acid (C18: degree of unsaturation 2), linolenic acid (C18: degree of unsaturation 3) should be used. Can be done. Such fatty acids are particularly desirable to be saturated fatty acids, but can be appropriately selected depending on the desired latent heat storage characteristics.

The alcohols used in the production of fatty acid esters are linear lower alcohols such as methanol and ethanol, branched alcohols such as 2-ethylhexanol, polyhydric alcohols such as propylene glycol, ethylene glycol and glycerin, and aromatics such as phenethyl alcohol. Alcohol can be used. Further, the alcohol can be used in the range of 2 to 30 carbon atoms.

Further, the transesterification reaction between the fatty acid and the alcohol can be carried out by a known method such as esterification under an alkali catalyst or an acid catalyst, and the transesterification reaction between the raw material fat and oil and the alcohol is sulfuric acid. It can be carried out by a known method such as transesterification using an acid such as hydrochloric acid or a base such as sodium hydroxide as a catalyst. However, the fatty acid ester is produced by a heterogeneous resin catalyst method in which a mixed solution of fat and alcohol is brought into contact with an ion exchanger (anion exchanger and / or a cation exchanger) and continuously produced. Is desirable. This is because a fatty acid ester having a desired melting point can be easily synthesized by using this method.

FIG. 1 shows the process flow of the conventional method and the method according to the present embodiment. The conventional phase-equal catalyst method requires as many complicated operations as the number of fatty acid esters to be mixed, such as a dehydration operation to prevent a decrease in catalytic activity and removal of catalysts and impurities. On the other hand, in the non-uniform phase catalyst method of this method, since a solid resin catalyst is used, it is easy to separate from the product, and impurities and water are adsorbed on the resin, so that the alcohol used in the reaction is distilled. The desired latent heat storage material can be obtained simply by removing it. Therefore, it can be said that this method is more effective than the conventional method.

In such an heterogeneous phase resin catalyst method, free fatty acids contained in fats and oils can be esterified using a cation exchanger as a catalyst. As the cation exchanger, for example, a cation resin known to those skilled in the art such as Diaion PK-208 (manufactured by Mitsubishi Chemical Corporation) can be used. Further, the triglyceride contained in the fat and oil can be transesterified by using an anion exchanger as a catalyst. As the anion exchanger, Diaion PA-306 (manufactured by Mitsubishi Chemical Corporation), Diaion PA-306S (same), Diaion PA-308 (same), Diaion HPA-25 (same), Diaion SA20A (same) Copper), Diaion SA21A (same), and porous type II strong base anion exchange resin, Diaion PA408 (same), Diaion PA412 (same) and Diaion PA418 (same), Dawex 1 An anionic resin known to those skilled in the art such as -X2 (manufactured by Dow Chemical Co., Ltd.), Amberlite IRA-45 (manufactured by Organo), Amberlite IRA-94 (same as above) can be used. It is desirable that these ion exchange resins have a small degree of cross-linking, and particularly preferably that the degree of cross-linking is 4% or less (in terms of molars).

However, when a fatty acid ester is produced using the above ion exchange resin, the alcohol or fatty acid used is melted at a temperature equal to or lower than the heat resistant temperature of the ion exchange resin, taking into consideration the heat resistant temperature of the ion exchange resin. It is desirable that it is a thing.

The latent heat storage material composition according to the present embodiment contains fatty acid esters as main components, and contains 1 wt% or more of each of the fatty acid and the fatty acid ester produced from the fatty acid and alcohol in the composition. Will be done. That is, it can be formed as a mixture of fatty acid and fatty acid ester. The latent heat storage material composition may further contain an alcohol, preferably an alcohol having a medium chain or higher having a phase change temperature close to each other.

The fatty acid content in the latent heat storage material composition is 75 wt% or more, particularly 80 wt% or more when the temperature of the phase change is concentrated at one point (that is, when the peak of the DSC curve is unified). Is desirable. However, when the temperature of the phase change is dispersed into two or more (that is, when the peak of the DSC curve is two or more), it may be less than 75 wt%.

Further, the latent heat storage material composition used in the present embodiment can be formed as a mixture of fatty acid and fatty acid ester as described above, and at least one of the fatty acid and alcohol for producing the fatty acid ester is two or more kinds. Combinations can be used. This makes it possible to obtain a mixed composition in which the fatty acid esters constituting the latent heat storage material composition are composed of a plurality of combinations.

The fatty acid ester used in the latent heat storage material composition can be produced not only by the esterification reaction of fatty acid and alcohol, but also by the transesterification reaction of raw material fat and oil and alcohol. In particular, when a fatty acid ester is produced from a raw material fat and oil, the free fatty acid in the raw material fat and oil can be esterified with alcohol, and the triglyceride in the raw material fat and oil can be ester-exchanged with alcohol to produce a fatty acid ester. In particular, when the fatty acid ester is produced by the reaction of the raw material fat and oil with alcohol, the content of the fatty acid ester in the latent heat storage material composition may be 1 wt% or more and 99 wt% or less. In particular, when the temperature of the phase change is concentrated at one point (that is, when the peak of the DSC curve is made one), the content of the fatty acid ester produced by the transesterification is 75 wt% or more, particularly 80 wt% or more. Is desirable. However, when the temperature of the phase change is dispersed in two or more (that is, when the peak of the DSC curve is two or more), the content of the fatty acid ester may be less than 75 wt%.

The desired latent heat storage characteristics are obtained by terminating the above esterification reaction or transesterification reaction when the fatty acid ester content (mixed mole fraction) in the composition reaches an arbitrary value. is there. Therefore, the esterification or transesterification reaction is terminated at the stage where the desired latent heat storage property is obtained, and a composition in which fats and oils and fatty acids as raw materials are mixed in addition to the fatty acid ester is produced. Normally, the latent heat is reduced because the peaks of the DSC curve are observed separately depending on the type of fatty acid or fatty acid ester mixed in the composition. However, in the present embodiment, the specific fatty acid ester can be in a eutectic state in which the DSC peak becomes one even if the fatty acid and the fatty acid ester produced from the fatty acid are mixed, whereby the latent heat can be obtained. Can be increased.

For such latent heat storage characteristics, for example, a plurality of mixtures in which the reaction rate (mole fraction) to a predetermined fatty acid ester is changed are prepared, and a melting curve or a solidification curve is obtained by measurement with a differential scanning calorimeter (DSC). The phase change temperature and transfer enthalpy at each reaction rate can be specified. Then, based on this measurement result, it is possible to specify the reaction rate (or mole fraction) having a phase change temperature in a target temperature region and having a desired latent heat.

When used as a latent heat storage material, it is desirable that there is one peak in the melting curve and solidification curve, and the latent heat (transfer enthalpy) obtained from the peak area is large. Further, it is desirable that the interval between the start point (temperature) and the end point (temperature) in the phase change is narrow, and therefore, in the melting curve, the interval between the melting start point (melting start temperature) and the melting end point (melting end temperature), In the solidification curve, it is desirable that the interval between the solidification start point (melting start temperature) and the solidification end point (melting end temperature) is narrow. Then, it is desirable that the peak appearing on the DSC curve (melting curve or solidification curve) has a sharp reaction rate. Here, "the peak is sharp" is a comparison on the DSC curve obtained under the same analysis conditions, and the reaction rate at which the peak becomes sharper when compared under the same analysis conditions is defined. Is desirable.

Experimental Example 1

〔experimental method〕
In this experiment, two types of (saturated) fatty acids widely contained in vegetable oils and their methyl and ethyl esters were taken up, and the thermal characteristics were measured in a two-component mixed system combining them to examine their effects on melting point and latent heat. did. The melting points and latent heats of the four fatty acid esters taken up are shown in Table 1 below.

The basic fatty acid skeleton is saturated palmitic acid (PA) having a carbon chain length of 16 and saturated stearic acid (SA) having a carbon chain length of 18, and their methyl esters (PM, SM) and ethyl esters (PE, SE). ). The mixed system was PM + SM, PM + PE, PM + SE as a system having a similar melting point. Thermal properties, the molar fraction of methyl palmitate (PM) to _{(X PM)} and the mixture was varied to 0.00 to 1.00 were prepared and measured with a differential scanning calorimeter (DSC). The temperature range was −20 ° C. to 60 ° C., and the heating rate was 10 ° C./min.

〔Results and discussion〕
FIG. 2 shows a melting curve in a PM + SM and PM + PE mixed system. The downward peak represents endothermic during the phase change. In the PM + SM system of (a), when the mixture of X _PM = 0.22, the peak became small and broad, and when X _PM = 0.61, two peaks for each component were observed. The tendency for this peak to be small and broad was also observed in the PM + SE system. On the other hand, in the PM + PE system (b), one large peak either _{X PM} were observed. From this, it is considered that this mixed system is in a eutectic state.

FIG. 3 shows the melting point (T _peak ) obtained from the peak top at each _XPM in FIG. 2 and the latent heat (ΔH) obtained from the peak area. It can be seen that in both systems, the melting point and the amount of latent heat decrease due to mixing. However, the degree of decrease varies from system to system. The dotted line in the figure is the living temperature range of a person. In the mixed system taken up this time, the condition that the melting point is in this temperature range and the latent heat is high is a mixture of X _PM = 0.20 in the PM + PE system.

Experimental Example 2

〔experimental method〕
In this experiment, ester synthesis using waste oil as a raw material, which is possible by using a method using an ion exchange resin as a catalyst, was performed, and the fatty acid composition and thermochemical properties of the obtained ester were examined. As the waste oil, four kinds of oils were used, which were stored as samples in an edible oil manufacturing plant for a predetermined period of time and then discarded. In ester synthesis, a reaction solution in which oil and alcohol are mixed in a stoichiometric ratio using the product name Diaion PA306S (porous, particle size 0.150 to 0.425 mm) manufactured by Mitsubishi Chemical Co., Ltd., which is a strong basic resin, as a catalyst. A 33 wt% strongly basic resin was added, and the mixture was sufficiently shaken at a reaction temperature of 50 ° C. Then, when the residual rate of the oil became 1% or less (that is, the conversion rate of the fatty acid group was 99% or more), the reaction was terminated, the strong basic resin was filtered off, and then the residual alcohol was distilled off.

Table 2 below (composition of methyl esters from various waste oils) shows the measurement results of the fatty acid composition of fatty acid esters synthesized from four types of waste oils. For reference, the melting point of each ester is also shown.

〔Results and discussion〕
The DSC melting curve by the differential scanning calorimeter for the fatty acid esters derived from the above four kinds of waste oils is shown in FIG. In the ester of each synthesized vegetable oil, multiple peaks derived from fatty acids with high content were observed, and those with saturated fatty acids having a melting point of 30 ° C or higher without double bonds and those with double bonds of -20 ° C or lower were not found. It contained saturated fatty acids. However, the number of components and the number of peaks do not match, and one peak is formed by the methyl form of palmitic acid (PA) and stearic acid (SA), such as the peak near 20 ° C of cocoa butter. Was also observed. It is desirable that the heat storage material for building materials has a melting point of about 10 to 30 ° C. and has one large peak of latent heat. Therefore, FIG. 5 shows the measurement results of the melting points of the cocoa butter-derived esters in comparison with the melting points of the pure fatty acid esters. It is considered that the large peak around 25 ° C corresponds to the melting point of the mixture of stearic acid and palmitic acid esters, and the two peaks around -40 ° C correspond to the melting points derived from the esters of oleic acid and linoleic acid. Be done.

Experimental Example 3

In this experiment, an esterification experiment of palmitic acid (PA) and a thermal analysis of the product were performed. The following equipment was used for the analysis in this experimental example.
"Analysis equipment"
-FAME concentration: Analyzer GC-FID (GL Sciences)
Column InertCap WAX-HT
Internal standard Methyl pentadecate (256.4 g / mol)
・ Acid value measurement: Analyzer automatic titration system AT-710 (Kyoto Denshi Kogyo Co., Ltd.)
Titration solution Ethanol 0.1 mol / L KOH solution / thermal analysis: Analyzer DSC 7000X (Hitachi High-Tech Science)

[Esterification experiment]
For palmitic acid, the product name 3ZINJ (purity 97.9%, 256.4 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. is used, and in the esterification experiment, the product name Diaion PK208LH manufactured by Mitsubishi Chemical Corporation, which is a strongly acidic resin, is used. Was used as a catalyst, and esterification was carried out under the following conditions.
"Experimental conditions for esterification"
Amount of methanol: 3 times the stoichiometric ratio Resin amount: 33 wt% of the total amount of reaction solution
Reaction temperature: 50 ° C
Shaking speed: Mix well (150 spm)

Specifically, the composition of the reaction solution (charged amount) used in the esterification experiment was palmitic acid (PA): 54.9 g, methanol: 21.1 g, and a strong acid resin catalyst (product name "Diaion" manufactured by Mitsubishi Chemical Corporation). PK208LH "): 37.8 g, which was reacted under the experimental conditions for esterification. Esterification was performed. Then, sampling was performed every hour from the start of the reaction to 12 hours, and further sampling was performed 28 hours after the start of the reaction to determine the palmitic acid concentration and the reaction rate. The result is shown in FIG. Table 3 below shows the reaction time and reaction rate.
The reaction rate was calculated by the following formula.
[Calculation of reaction rate]

[Thermal analysis experiment]
Each sample in the above esterification experiment was measured with a differential scanning calorimeter (DSC) to obtain a solidification curve and a melting curve at each reaction rate (palmitic acid reaction rate: _YPM ). The result is shown in FIG. Further, from the solidification curve and the melting curve shown in FIG. 7, the peak top temperatures of the solidification and melting peaks (T _{peak, f} , T _{peak, m} , respectively) are obtained, and the latent heat of solidification and melting (ΔH _f , respectively ₎ . ΔH _m ) was determined, and the results are shown in Table 4 and FIG. 8 below.

In FIG. 8, in the DSC curve, the solidification start point of the solidification curve, _{Tonset, f} (◯ in the drawing), and the melting end point of the melting curve, _{Toffset, m} (□ in the drawing), are shown. The peak on the highest temperature side of the DSC differential values is set as the maximum inclination point of the DSC curve, and is the value of the intersection between the tangent line and the baseline (the tangent line of the point where the DSC value is less than 1.0 mW / mg). The _{Toffset, f} (□ in the drawing), which is the solidification end point of the solidification curve, and the _{Tonset, m} (○ in the drawing), which is the melting start point of the melting curve, are located on the lowest temperature side of the DSC differential values. A certain peak is set as the maximum inclination point of the DSC curve, and is the value of the intersection with the baseline (the tangent line of the point where the DSC value is less than 1.0 mW / mg).

[Discussion]
When esterification was performed using palmitic acid as a fatty acid, one peak derived from methyl palmitate was produced in a temperature range of a reaction rate of 0.821 (reaction time 7 hours) or higher and a temperature range of 15 ° C. or higher and 25 ° C. or lower. It was confirmed that it had a large latent heat of about 180 J / g. It was also confirmed that as the reaction rate decreased, the heat storage temperature region increased and the latent heat decreased, and as the reaction rate approached 1.0, the heat storage temperature region increased and the latent heat also increased.

Experimental Example 4

In this experiment, an esterification experiment was carried out by the same treatment as in Experimental Example 3 using two kinds of alcohols, and a thermal analysis of the product was carried out. That is, an esterification experiment with palmitic acid (PA) and a mixed alcohol (methanol and ethanol) and a thermal analysis of the product were performed. The analyzer in this experimental example is the same as that in experimental example 3.

[Esterification experiment]
For palmitic acid, product name 3ZINJ (purity 97.9%, 256 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. was used, and for methanol, Wako Pure Chemical Industries, Ltd. , Manufactured by the company (≧ 99.5 vol%, 32.04 g / mol1), ethanol is Japan Alcohol Corp. , Ltd. , Company-made (≧ 99 vol%, 46.1 g / mol1) was used. In addition, the experimental conditions for the strongly acidic resin and esterification are the same as those in Experimental Example 3.

In particular, the composition of the reaction solution (charged amount) used in the esterification experiment was palmitic acid (PA): 66.9 g, methanol: 19.9 g (alcohol molar ratio: 0.797), ethanol: 7.3 g (alcohol molar). Ratio: 0.203), strong acid resin catalyst (product name "Diaion PK208LH" manufactured by Mitsubishi Chemical Co., Ltd.): 47.1 g was used.

Then, an esterification reaction is carried out, sampling is performed every hour from the start of the reaction to 12 hours, and further sampling is performed 28 hours after the start of the reaction. Fatty acid esters (methyl palmitate, ethyl palmitate, And the concentration of total ester) and the reaction rate were determined. The result is shown in FIG. Table 5 below shows the reaction time and reaction rate.

[Thermal analysis experiment]
In the same manner as in Experimental Example 3, each sample in the above esterification experiment was measured with a differential scanning calorimeter (DSC) to obtain a solidification curve and a melting curve at each reaction rate (palmitic acid reaction rate: Y _PM ). The result is shown in FIG. Further, from the solidification curve and the melting curve shown in FIG. 10, the peak top temperatures of the solidification and melting peaks (T _{peak, f} , T _{peak, m} , respectively) are obtained, and the latent heat of solidification and melting (ΔH _f , respectively ₎ . ΔH _m ) was determined, and the results are shown in Table 6 and FIG. 11 below.

[Discussion]
It was found that when the fatty acid groups were the same and the alcohol groups were changed, the mixture had a tendency for the peak rise to convergence on the DSC curve to be narrower. And if the peak is sharp in the target temperature range (the peak rise to convergence tends to be narrow), the latent heat amount tends to increase, so the performance as a heat storage material (latent heat storage characteristic) becomes high. It was confirmed.

Experimental Example 5

In this experiment, using two kinds of fatty acids, an esterification experiment was carried out by the same treatment as in Experimental Example 3, and the product was thermally analyzed. That is, an esterification experiment was carried out using a mixed fatty acid of palmitic acid (PA) and stearic acid (SA) and methanol, and the product was thermally analyzed. The analyzer in this experimental example is the same as that in experimental example 3.

[Esterification experiment]
For palmitic acid, product name 3ZINJ (purity 97.9%, 256 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. is used, and for stearic acid, product name FL3YJ (purity 97.0%, 284.) manufactured by Tokyo Chemical Industry Co., Ltd. is used. 5 g / mol1) was used, and methanol was used in Wako Pure Chemical Industries, Ltd. , (≧ 99.5 vol%, 32.0 g / mol1) manufactured by the company was used. In addition, the experimental conditions for the strongly acidic resin and esterification are the same as those in Experimental Example 3. The mixed fatty acid was PA: SA = 80 mol%: 20 mol% on a mass basis.

In particular, the composition of the reaction solution (charged amount) used in the esterification experiment was palmitic acid (PA): 54.1 g (fatty acid molar ratio: 0.800), stearic acid (SA): 15.0 g (fatty acid molar ratio:). 0.200), methanol: 25.3 g, strong acid resin catalyst (product name "Diaion PK208LH" manufactured by Mitsubishi Chemical Co., Ltd.): 47.1 g was used.

Then, an esterification reaction is carried out, sampling is performed every hour from the start of the reaction to 12 hours, and further sampling is performed 28 hours after the start of the reaction. Fatty acid esters (methyl palmitate, methyl stearate, And the total ester) concentration and reaction rate were determined. The result is shown in FIG. Table 7 below shows the reaction time and reaction rate.

[Thermal analysis experiment]
In the same manner as in Experimental Example 3, each sample in the above esterification experiment was measured with a differential scanning calorimeter (DSC) to obtain a solidification curve and a melting curve at each reaction rate (fatty acid reaction rate: _YFA ). The result is shown in FIG. Further, from the solidification curve and the melting curve shown in FIG. 13, the peak top temperatures of the solidification and melting peaks (T _{peak, f} , T _{peak, m} , respectively) are obtained, and the latent heat of solidification and melting (ΔH _f , respectively ₎ . ΔH _m ) was determined, and the results are shown in Table 8 and FIG. 14 below.

[Discussion]
When the reaction rate (Y _FA ) of fatty acid is 0.80 or more, the peak tends to be single in the DSC curve, and the temperature interval between the phase change start point ( _Tonset ) and the phase change end point ( _Toffset ) is Since the peak is narrow, the peak tends to be large, so that the heat storage and heat storage performance in the target temperature range is high.
Further, in consideration of the above-mentioned Experimental Example 4, as a combination of fatty acid esters, the combination of methyl palmitate and ethyl palmitate has a better peak as described above in the DSC curve than the combination of methyl palmitate and methyl stearate. It was confirmed that there is a high tendency to become.

Experimental Example 6

In this experiment, using two kinds of fatty acids, an esterification experiment was carried out by the same treatment as in Experimental Example 3, and the product was thermally analyzed. That is, an esterification experiment was carried out using a mixed fatty acid of palmitic acid (PA) and stearic acid (SA) and ethanol, and the product was thermally analyzed. The analyzer in this experimental example is the same as that in experimental example 3.

[Esterification experiment]
For palmitic acid, the product name 3ZINJ (purity 97.9%, 256.4 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. is used, and for stearic acid, the product name FL3YJ (purity 97.0%) manufactured by Tokyo Chemical Industry Co., Ltd. is used. , 284.48 g / mol1), and ethanol was used in Japan Alcohol Corp. , Ltd. , Company manufactured (≧ 99 vol%, 46.07 g / mol1) was used. In addition, the experimental conditions for the strongly acidic resin and esterification are the same as those in Experimental Example 3. The mixed fatty acid was PA: SA = 80 mol%: 20 mol% on a mass basis.

In particular, the composition of the reaction solution (charged amount) used in the esterification experiment was palmitic acid (PA): 54.1 g (fatty acid molar ratio: 0.800), stearic acid (SA): 15.0 g (fatty acid molar ratio:). 0.200), ethanol: 25.3 g, strong acid resin catalyst (product name "Diaion PK208LH" manufactured by Mitsubishi Chemical Co., Ltd.): 47.1 g was used.

Then, an esterification reaction is carried out, sampling is performed every hour from the start of the reaction to 12 hours, and further sampling is performed 28 hours after the start of the reaction. Fatty acid esters (methyl palmitate, methyl stearate, And the total ester) concentration and reaction rate were determined.

[Thermal analysis experiment]
In the same manner as in Experimental Example 3, each sample in the above esterification experiment was measured with a differential scanning calorimeter (DSC) to obtain a solidification curve and a melting curve at each reaction rate (fatty acid reaction rate: _YFA ). The result is shown in FIG. Further, from the solidification curve and the melting curve shown in FIG. 15, the peak top temperatures of the solidification and melting peaks (T _{peak, f} and T _peak, respectively) are obtained, and the latent heat of solidification and melting (ΔH _f , respectively ₎ . ΔH _m ) was determined, and the results are shown in Table 9 and FIG. 16 below.

[Discussion]
When the reaction rate (Y _FA ) of fatty acid is 0.80 or more, the peak tends to be single in the DSC curve, and the temperature interval between the phase change start point ( _Tonset ) and the phase change end point ( _Toffset ) is Since the peak is narrow, the peak tends to be large, so that the heat storage and heat storage performance in the target temperature range is high.

The latent heat storage material composition of the present invention and the method for controlling the latent heat storage characteristics are used in various fields such as building materials such as heat storage sheets for building materials, textile products, and thermal stability in an arbitrary temperature range. Can be used in. Further, the latent heat storage material composition and the latent heat storage characteristic control method of the present invention obtain latent heat storage characteristics in a living temperature range of 15 ° C. to 25 ° C., as well as a freezing temperature range (low temperature range) or a heating temperature range (low temperature range). It can be used to obtain thermal stability in a wide temperature range such as (high temperature range).

Claims (5)

1. A latent heat storage material composition containing fatty acid esters as a main component.
   It consists of a fatty acid and a fatty acid ester produced from the fatty acid and alcohol.
   A latent heat storage material composition in which the content of fatty acid and fatty acid ester is 1 wt% or more in the composition, respectively.
   
2. A latent heat storage material composition containing fatty acid esters as a main component.
   The fatty acid esters are latent heat storage material compositions produced by one alcohol and two or more fatty acids, two or more alcohols and one fatty acid, or two or more alcohols and two or more fatty acids.
   
3. A latent heat storage material composition containing fatty acid esters as a main component.
   It consists of raw material fats and oils, and fatty acid esters produced from the raw material fats and oils and alcohol.
   A latent heat storage material composition having a fatty acid ester content of 1 wt% or more and 99 wt% or less in the composition.
   
4. It is a method of controlling the latent heat storage characteristics of the latent heat storage material.
   The latent heat storage material is composed mainly of fatty acid esters.
   The fatty acid esters are produced by an esterification reaction or a transesterification reaction, and a method for controlling the latent heat storage characteristics, in which the latent heat storage characteristics are controlled by the reaction rate to the fatty acid ester in any of the reactions.
   
5. A method for producing a latent heat storage material composition containing fatty acid esters as a main component.
   A method for producing a latent heat storage material composition, which comprises continuously producing a fatty acid ester using the ion exchanger as a catalyst by contacting a raw material fat or oil or a mixed solution of a fatty acid and an alcohol with the ion exchanger.

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