JP2016196578A - Latent heat storage material composition, latent heat storage body, heat storage floor heating and air conditioning system - Google Patents

Abstract

An object of the present invention is to prevent the latent heat storage material from exuding or phase separation from the support material even under a heat cycle in which the performance of the latent heat storage material is not impaired by the support on the support material and the phase transition due to solidification and melting is repeated. And a latent heat storage material composition capable of maintaining a stable gel state, and a latent heat storage body. The latent heat storage material composition of the present invention carries a latent heat storage material (A) composed of n-paraffin having 12 to 50 carbon atoms and a latent heat storage material (A) of 50 mass% to 94 mass%. The support material (B) includes a hydrogenated styrene-ethylene / propylene block copolymer in a proportion of 6 mass% to 50 mass%. [Selection figure] None

Description

  The present invention uses a latent heat storage material composition, particularly an n-paraffin having 12 to 50 carbon atoms as a latent heat storage material, and the n-paraffin is immobilized by a support material containing a thermoplastic elastomer. The present invention relates to a material composition, a latent heat storage body using a latent heat storage material composition, a heat storage type floor heating, and an air conditioning system.

  A technique that utilizes the phase change latent heat of a substance for heat storage is known. Among them, the technique using the latent heat of phase transition of n-paraffin has a wide range of living environment temperature (-20 ° C to 100 ° C) by appropriately selecting n-paraffin having a carbon number of 12 or more and 50 or less. ) Can be used, has a high heat storage density, has excellent characteristics such as no deterioration of properties and no corrosiveness even when the phase change is repeated.

  As a heat storage material utilizing the excellent characteristics of n-paraffin, a heat storage material has been proposed in which a thermoplastic elastomer is used as a support material and n-paraffin is fixed (gelled) by melt kneading.

  Of the thermoplastic elastomers, the graft-block copolymer or block copolymer contains at least one ethylene bond which may be one or more optionally conjugated, for example selected from ethylene or dienes such as butadiene and isoprene. Included are those comprising at least one block resulting from the polymerization of certain ethylenic monomers with at least one vinyl polymer block, and more suitably with a styrene polymer block. When the ethylenic monomer contains two or more ethylene bonds that may optionally be conjugated, the ethylene bonds remaining after polymerization are generally hydrogenated after polymerization. Thus, in known methods, the polymerization of isoprene results in the formation of ethylene-propylene blocks after hydrogenation, and the polymerization of butadiene results in the formation of ethylene-butylene blocks after hydrogenation.

As such a thermoplastic elastomer, for example, polystyrene-polyisoprene (hereinafter sometimes abbreviated as “SI”), polystyrene-polybutadiene (hereinafter referred to as “SI”) sold by BASF under the name of “Luvitol HSB”. “Diblock” or “Triblock” type, such as “SB”, and polystyrene-ethylene / propylene (hereinafter abbreviated as “SEP”) sold by Kraton Polymer Japan under the name “Kraton” Kraton G1701EU, G1702HU, 1651HU), polystyrene-ethylene / butylene (hereinafter abbreviated as “SEB”), polystyrene-ethylene / butylene-styrene (hereinafter abbreviated as “SEBS”; Kraton) G1651 U) "diblock" or "triblock" type block copolymer, and the like, such as.
These thermoplastic elastomers are generally known as hydrogenated or non-hydrogenated diene copolymers.

  In recent years, styrene-ethylene / butylene-styrene block copolymer (SEBS), ethylene-ethylene / butylene-ethylene block copolymer (hereinafter referred to as “CEBC”) is one type of support material made of thermoplastic elastomer. A heat storage material composition that uses a hydrogenated diene copolymer such as that described above has been developed (see, for example, Patent Documents 1 to 4).

JP-A-3-66788 International Publication No. 2011/078340 JP 2014-111746 A JP 2014-122320 A

  However, when SEBS or CEBC is used as a carrier, it is sealed in a synthetic resin container, and the temperature is repeatedly raised and lowered across the phase transition temperature. In some cases, problems such as discharge and phase separation may occur, and further improvements are desired. Patent Documents 3 and 4 exemplify polystyrene-ethylene / propylene (SEP) as an example of a hydrogenated diene copolymer, but no mention is made as to whether it can be used as a support material for heat cycle. It has not been.

  The object of the present invention is that there is no oozing or phase separation from the support material of n-paraffin, which is a latent heat storage material (high compatibility), even under a heat cycle in which the phase transition between solidification and melting is repeated many times, and the latent heat An object of the present invention is to provide a latent heat storage material composition, a latent heat storage body, a thermal storage floor heating system, and an air conditioning system that can maintain a stable gel state even when the heat storage material is mixed with the support material at a high concentration.

  As a result of diligent studies to solve the above problems, the present inventors have used n-paraffin having 12 to 50 carbon atoms as a latent heat storage material, and styrene-ethylene / propylene as a support material for the latent heat storage material. It has been found that by using a block copolymer in a predetermined ratio, a latent heat storage material composition having high compatibility and gel stability even under a heat cycle and a latent heat storage body can be obtained, and the present invention is completed. It came to.

  That is, the present invention is a latent heat storage material composition comprising a latent heat storage material (A) capable of storing heat by latent heat and a support material (B) carrying the latent heat storage material (A), wherein the latent heat storage material (A) is composed of n-paraffin having 12 to 50 carbon atoms, and the support material (B) is a styrene-ethylene / propylene block copolymer, and the latent heat storage material (A) is 50% by mass. It is characterized by comprising 94% by mass or less and the support material (B) in a proportion of 6% by mass or more and 50% by mass or less.

  Moreover, the latent heat storage body of the present invention is characterized by filling the packaging material with the latent heat storage material composition described above.

  According to the present invention, the latent heat storage material composition has high compatibility and gel stability even under a heat cycle, does not significantly decrease the latent heat amount due to mixing with the support material, and does not impair the performance of the latent heat storage material. It becomes possible to provide a latent heat storage body.

  Preferred embodiments of the latent heat storage material composition and the latent heat storage body according to the present invention will be described in more detail. However, the description of the constituent elements described below is an example of the embodiment of the present invention. Is not limited to these contents, and various modifications can be made within the scope of the gist thereof.

  The latent heat storage material composition according to the present invention is a latent heat storage material composition comprising a latent heat storage material (A) capable of storing heat by latent heat and a support material (B) carrying the latent heat storage material (A). The latent heat storage material (A) is made of n-paraffin having 12 to 50 carbon atoms, the support material (B) is a styrene-ethylene / propylene block copolymer, and the latent heat storage material (A) is 50 The support material (B) is contained in a proportion of 6% by mass or more and 50% by mass or less.

<Latent heat storage material (A)>
First, the latent heat storage material (A) will be described. The latent heat storage material (A) according to the present invention is n-paraffin having 12 to 50 carbon atoms. These n-paraffins are usually obtained from a petroleum fraction by rectification. Due to the limitations of the refining technology, n-paraffins with each carbon number may contain n-paraffins with adjacent carbon number of several mass%, but they are used as the latent heat storage material (A) of the present invention. There is no hindrance. The n-paraffin used as the latent heat storage material (A) may be synthesized, but it is simpler and cheaper to use one derived from a petroleum fraction. Hereinafter, in the present specification, a specific carbon number is determined without particularly distinguishing n-paraffins containing impurities of about several mass% obtained by rectification, or n-paraffins having high purity obtained by synthesis. It is described as having n-paraffin.

  The n-paraffin particularly useful as the latent heat storage material (A) is an n-paraffin having a phase transition temperature in the range of -10 ° C. to 30 ° C. in the range of cold insulation to residential environment temperature and having 12 to 18 carbon atoms. For example, it is preferable that the ratio of n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, and n-octadecane is 50% by mass or more. Particularly preferred as the latent heat storage material (A) is a material mainly containing n-tetradecane, n-hexadecane and n-octadecane having a large amount of latent heat of phase transition and an even number of carbon atoms.

  The latent heat storage material (A) is more preferably one in which the ratio of n-paraffins having 14 to 18 carbon atoms is 50% by mass or more, consisting of n-paraffins having 14 to 18 carbon atoms, and this Particularly preferred are those containing 50% by mass or more of any n-paraffin in the range, particularly n-tetradecane, n-hexadecane, or n-octadecane.

  The latent heat storage material (A) is made of n-paraffin having 14 to 18 carbon atoms and any n-paraffin, particularly n-tetradecane, n-hexadecane, or n-octadecane in this range. What contains 95 mass% or more is still more preferable.

<Supporting material (B)>
Next, the carrying material (B) carrying the latent heat storage material (A) will be described. The support material (B) is a styrene-ethylene / propylene block copolymer (B1).

  The basic structure of the styrene-ethylene / propylene block copolymer (B1) is an amorphous structure due to the presence of a hard segment block that is a crystalline structure having styrene as a repeating unit and a branch derived from a conjugated diene compound even after hydrogenation treatment. Which has a soft segment block. If the structure is determined by 1H-NMR, the amount of hydrogen atoms detected in the olefin region is extremely small (several percent or less). The styrene-ethylene / propylene block copolymer (B1) according to the present invention is preferably a styrene-ethylene / propylene block copolymer (SEP) using isoprene as a conjugated diene. For example, Kraton Polymer Japan Co., Ltd. ) From Clayton (registered trademark) G (SEP type), “1701EU”, “1702HU”.

  The styrene-ethylene / propylene block copolymer (B1) preferably has a melting peak derived from a hard segment when measured by a differential scanning calorimetry (DSC method) and melts in the range of 80 to 120 ° C. More preferably, it has a peak. The styrene-ethylene / propylene block copolymer (B1) in which this peak is not detected may lack the supporting function as the supporting material (B).

  The styrene-ethylene / propylene block copolymer (B1) according to the present invention can be used alone or in combination of two or more.

  As described above, the support material (B) according to the present invention is an n-paraffin support by using the styrene-ethylene / propylene block copolymer (B1) excellent in supportability of the latent heat storage material (A). Excellent characteristics can be ensured.

<Latent heat storage material composition>
The heat storage material composition according to the present invention comprises the latent heat storage material (A) in a proportion of 50 mass% to 94 mass% and the support material (B) in a ratio of 6 mass% to 50 mass%. When the ratio of the latent heat storage material (A) is less than 50% by mass or the ratio of the support material (B) is more than 50% by mass, a sufficient amount of heat storage may not be ensured. Further, when the ratio of the latent heat storage material (A) is greater than 94% by mass or the ratio of the support material (B) is less than 6% by mass, the latent heat storage material (A) may leak from the support material (B). There is. A latent heat storage material composition comprising the latent heat storage material (A) in a proportion of 50 mass% to 94 mass% and the support material (B) in a ratio of 6 mass% to 50 mass% is preferable.

  Subsequently, the production of the latent heat storage material composition according to the present invention will be described. The heat storage material composition according to the present invention is obtained by forcibly kneading, preferably melt-kneading a predetermined amount of latent heat storage material (A) and styrene-ethylene / propylene block copolymer (B1) by mechanical means. be able to.

  The melt kneading is preferably performed at least at a temperature at which the latent heat storage material (A) and the styrene-ethylene / propylene block copolymer (B1) are melted. As long as mixing is mixing by mechanical means, any of various mixing means is adopted, and typical means are stirring, mixing, and kneading, and equipment having the functions includes a stirrer, a mixer, and a kneading machine. And the two rolls used for rubber processing or thermoplastic resin processing, a Banbury mixer, an extruder, a biaxial kneading extruder, etc. are mentioned.

  The latent heat storage material composition obtained by the above method is then molded into an appropriate shape to form a latent heat storage material assembly. The latent heat storage material composition is appropriately shaped according to the intended use of the latent heat storage material composition, but the latent heat storage material composition according to the present invention can be attached to any shape, and can be packaged in any manner. It can also be used as a latent heat storage body filled with a material. In particular, filling a packaging material made of a transparent synthetic resin having a thickness of about 0.01 to 1 mm makes it easy to observe the phase transition from the outside, and a packaging material of a certain size. It is preferable to fill the, since it is possible to make a latent heat storage body having a certain standard in which contact with outside air is blocked and oxidation deterioration is suppressed. From this viewpoint, a preferable packaging material is a packaging material made of a synthetic resin film in which oxygen permeability is suppressed, for example, a packaging material made of a multilayer film containing polyamide.

  Further, the latent heat storage material composition according to the present invention is added to the heat storage material composition using other thermoplastic elastomer or thermoplastic resin (for example, low crystalline α-olefin-ethylene copolymer). Needless to say, various additives, fillers, and the like can be added.

  The latent heat storage body which filled the packaging material with the latent heat storage body composition which concerns on this invention can be used for a thermal storage type floor heating apparatus. For example, a latent heat storage body is installed between a foundation floor having a heat insulating material layer and the floor material, and the latent heat storage material is heated to a temperature equal to or higher than the melting point of the latent heat storage material (A) by heating means such as a surface heater. By storing heat in the body, it can be used as a regenerative floor heater.

  Moreover, the latent heat storage body which filled the packaging material with the latent heat storage body composition which concerns on this invention can be used for an air conditioning system. For example, it can be used as an air conditioning system by supplying air conditioning refrigerant cooled or heated by an air conditioner to a heat exchanger in which a latent heat storage body is disposed and exchanging heat with the latent heat storage body to store heat. .

  The present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

Each chemical used in the examples was obtained from the market without purification. Hereinafter, the latent heat storage material (A) used in the examples, the styrene-ethylene / propylene block copolymer (B1), the styrene-ethylene / butylene-styrene block copolymer (B2) used in the comparative examples, and ethylene. -An ethylene / conjugated diene-ethylene block copolymer (B3) is shown.
<Latent heat storage material (A)>
n-Tetradecane (C14) (“TS-4 (trade name)” manufactured by JX Nippon Oil & Energy Corporation)
n-Hexadecane (C16) (“TS-6 (trade name)” manufactured by JX Nippon Oil & Energy Corporation)

<Styrene-ethylene / propylene block copolymer (B1)>
Clayton G1701EU (manufactured by Clayton Polymer)

<Styrene-ethylene / butylene-styrene block copolymer (B2)>
Clayton G1651HU (manufactured by Clayton Polymer)

<Ethylene-ethylene / conjugated diene-ethylene block copolymer (B3)>
Dynalon (registered trademark) 6360B (manufactured by JSR)

<Manufacture of latent heat storage material composition>
The latent heat storage material (A), the styrene-ethylene / propylene block copolymer (B1), the styrene-ethylene / butylene-styrene block copolymer (B2), ethylene, in the types and blending amounts shown in Table 1 and Table 2. -Melt-kneading a support material (B) selected from ethylene / conjugated diene-ethylene block copolymer (B3) to produce latent heat storage material compositions according to Examples 1 to 6 and Comparative Examples 1 to 7 did. The melt-kneading was performed for 60 minutes using a sealed chamber at a rotation speed of 300 rpm and a temperature of 90 ° C.

<Heat cycle test>
After heat-melting the latent heat storage material composition produced by the formulations of Examples 1 to 6 and Comparative Examples 1 to 7, it was poured into a thin glass tube (φ = 5 mm), solidified by lowering to room temperature, and heat cycle test It was set as the evaluation sample. For each n-paraffin melting point contained in each latent heat storage material composition, a constant temperature bath A in the range of −5 to −15 ° C. or lower and a constant temperature bath B in the range of +5 to + 15 ° C. or higher are prepared, The evaluation samples were alternately immersed in the thermostats A and B, and the phase transition of the latent heat storage material composition was repeated up to 300 times, and then the presence or absence of phase separation was evaluated. In the heat cycle test, the evaluation sample was immersed in a constant temperature bath A having a temperature lower than the melting point, and after confirming the solidification / solidification phase transition of n-paraffin in the latent heat storage material composition by visual observation (whitening of the entire composition) ), Immersing the evaluation sample in a constant temperature bath B having a temperature higher than the melting point, and visually confirming the dissolution and liquefaction phase transition of the n-paraffin in the latent heat storage material composition (solidification of the entire composition) And liquefaction was repeated once (300 times). The material in which the latent heat storage material (A) did not bleed out (occurrence of phase separation) after 300 heat cycles was evaluated as “◯”, and the material that bleeded out (occurrence of phase separation) in less than 300 times was evaluated as “x”. In addition, the temperature difference of both thermostats is the range of 15 to 30 degreeC in general. The results are shown in Tables 1 and 2.

  The latent heat storage material composition according to Examples 1 to 6 is obtained by changing the type and addition amount of n-paraffin used for the latent heat storage material (A). The obtained latent heat storage material composition showed no fluidity in the liquid confirmation test at 20 ° C. of the Fire Service Act, and no n-paraffin bleed was observed. In the heat cycle test, no bleed out was observed up to 300 times. Furthermore, the amount of latent heat of Example 1 was 210 J / g, which was 11 to 13 J / g higher than Comparative Examples 3 and 4 using the same latent heat storage material (A) at the same ratio. In Example 4, the amount of latent heat was 221 J / g, which was 21 J / g higher than that of Comparative Example 6 having the same composition ratio.

  The latent heat storage material composition of Comparative Example 1 is obtained by changing the amount of n-paraffin added to the latent heat storage material (A) to 5% by mass. In Comparative Examples 2-3, 5-10% by mass of styrene-ethylene / butylene-styrene block copolymer (B2) was used as the support material (B). In Comparative Examples 4 to 7, the type and amount of n-paraffin used in the latent heat storage material (A) were changed, and the support material (B) was changed to ethylene-ethylene / conjugated diene-ethylene block copolymer (B3). It is a thing. Comparative Example 1 exhibited fluidity in a liquid confirmation test at 20 ° C. according to the Fire Service Act, and corresponded to a dangerous substance in the Fire Service Act. Comparative Examples 2-7 did not show fluidity in the liquid confirmation test at 20 ° C. of the Fire Service Act. In the heat cycle test, in Comparative Examples 1 to 4, 6 and 7, n-paraffin bleed out occurred less than 300 times, but in Comparative Example 5, no n-paraffin bleed was observed, and the heat cycle test Also, no bleed out was observed up to 300 times. In Comparative Example 5, the amount of latent heat was 182 J / g, which was 10 J / g lower than Example 2 using the same latent heat storage material (A) at the same ratio.

  As described above, n-paraffin is used as the latent heat storage material (A), the styrene-ethylene / propylene block copolymer (B1) is included as the support material (B), and the latent heat storage material (A) and the support material are included. The latent heat storage material composition of the present invention comprising (B) at a predetermined ratio not only has a high heat storage density in the cold insulation to residential environment temperature range, but also reduces the occurrence of bleed out even under a heat cycle. Can do.

The latent heat storage material composition and latent heat storage body of the present invention can be suitably used for various applications such as a heat storage type floor heating system and an air conditioning system.

Claims (6)

  A latent heat storage material (A) composed of n-paraffin having 12 to 50 carbon atoms that can store heat by latent heat is a support material (B) that supports 50 to 94 mass% of the latent heat storage material (A). A latent heat storage material composition comprising a styrene-ethylene / propylene block copolymer in a proportion of 6% by mass to 50% by mass. 2. The latent heat storage material composition according to claim 1, wherein the ratio of n-paraffin having 12 to 18 carbon atoms is 50 mass% or more in the latent heat storage material (A). 2. The latent heat storage material composition according to claim 1, wherein the ratio of n-paraffin having 14 to 18 carbon atoms in the latent heat storage material (A) is 50 mass% or more.   A latent heat storage body comprising the packaging material filled with the latent heat storage material composition according to any one of claims 1 to 3.   Heat storage type floor heating using the latent heat storage body according to claim 4. An air conditioning system using the latent heat storage body according to claim 4.