JPS58138772A - Heat storing material - Google Patents

Abstract

PURPOSE:An inexpensive heat storing material, consisting of acetic acid and glycollic acid, capable of controlling the heat storage temperature and heat radiation temperarure depending on the composition, having the stable heat absorbing and radiating performance and large heat quantity of storage, and suitable for cooling and heating, etc. CONSTITUTION:A heat storing material consisting of acetic acid (CH3COOH) and preferably 35wt% or less (except 0wt%) glycollic acid (HOCH2COOH).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat storage material made of CH3COOH and HOCH2COOH.

In general, there are two types of heat storage materials known: those that utilize the sensible heat of substances and those that utilize latent heat. Heat storage materials that use latent heat have a larger amount of heat storage per unit weight and unit volume than heat storage materials that use sensible heat, and require only a small amount of heat storage material to store the required amount of heat. Therefore, it is possible to downsize the heat storage device. Furthermore, unlike heat storage materials that utilize sensible heat, this material has the characteristic of radiating heat at a constant temperature at a transition point, without causing the temperature to drop as heat is radiated.

By the way, conventionally, 0H3COOH (acetic acid) is 16
．． It has a melting point of 7℃ and a latent heat of about 450111/,! i+
It is known to be a large substance. but,
Since CHsCOOH has a high melting point of 16.7° C., it has been difficult to put it into practical use as a heat storage material for air conditioning.

The present invention provides a heat storage material that is inexpensive, has stable heat absorption and radiation performance, and has a large amount of heat storage, in which the heat storage temperature and heat radiation temperature can be controlled by changing the composition of the system consisting of H3COOH and HO (iH2cOOH). Its characteristics are 0H3COOH and HO(
H2COO)! It is based on a two-component system consisting of
It is particularly desirable that the weight percentage is 35% or less (excluding 0%) with respect to the total amount with 3cooH.

An example of the present invention will be described below in comparison with a comparative example.

Commercially available reagent grade C)13COOH and)IOCH2CO
Using OH, a predetermined amount was mixed as shown in Table 1, and it was heated at 40' (,!) to dissolve as much solid matter as possible and used as a sample.The magnitude of latent heat and transition temperature of these samples was measured using a differential scanning calorimeter (D, S, C,).

The magnitude of latent heat is determined from the area of the endothermic part of the DSC curve,
The transition temperature was determined from the temperature of the endothermic peak. The results are shown in Table 2. In Table 2, if the sample undergoes a transition at two temperatures, those temperatures are listed. In addition, the latent heat is the sum of the heat due to these transitions. By the way, it goes without saying that the transition below 0°C is
In this case, it was considered unnecessary, so it was removed.

The evaluation in Table 2 is for samples with a latent heat of 30ca17g or more, but the samples marked with O have a large amount of heat storage and can be easily put to practical use, and the samples marked with Δ have a large amount of heat storage. Although it is not very large, it is considered that it can be put into practical use sufficiently.

Margin below? Table 1 However, * Comparative Example Table 2 Analyzing the data in Table 2 shows that cn5coon has HO
Sample 1 with CH2COOH added at 0.25 wt% is
The melting point drops to 16.2℃ and the latent heat is 45 cal/g.
and 0, which is almost the same as OH5cOOH, and
As the content of HOCH2COOH increases, “H
oe) The latent heat decreases little by little until Sample 5 has an I2COOH content of swt%. However, this change is very small. At this time, the transition temperature also decreases. and.

Sample 6 with HOCiH2COOH content of 7.6 wt%
As the temperature increases, the latent heat increases again, and the latent heat reaches 490,317 g in sample 7 with a HOCH2COOH content of 10 wt%.

Furthermore, even if the content of ) IOCH2COOH is increased, the latent heat does not increase but gradually decreases. Transition temperature 1
1(4,HOCH2COOH) content is 1o, owt%
Up to sample 7, it decreases as the HOCH2000H content increases. However, even if the content of HOCH2COOH is increased further, the transition point does not change.
It remains constant around 7℃.

To summarize the above, in the evaluation column of Table 2, the composition regions of the samples marked with Δ and ○ are OH, Cool and HOCH.
In the binary system of 2Ci00H, HOCH2COOH
It is desirable that the content is greater than □wt% and less than 35wt%.

Next, 1wt% of ycHocH2cooH was contained.

700 g of a mixture having the same composition as sample 7 with an inner diameter of 100 mm.

It was stored in a cylindrical container with a height of 100 mm and sealed with a stopper equipped with a thermocouple insertion front. When the container was repeatedly heated and cooled between 0°C and 20'C, it repeatedly melted and solidified stably, and the heat storage material of the present invention did not have any problems even in continuous use, and it showed stable absorption. It was confirmed that it has heat dissipation performance.

As mentioned above, the present invention provides OH3Cool and HOCH2
It is composed of two components of COOH, and by changing their composition, the heat storage temperature and heat radiation temperature can be controlled, and it provides a heat storage material that is inexpensive, has stable heat absorption and radiation performance, and has a large amount of heat storage. In addition, in the present invention, other melting point depressants may be used together, or a supercooling prevention agent may be used, a thickening agent may be used to prevent the supercooling prevention agent from settling or agglomeration, or other additives may be used. It goes without saying that agents and the like may be added as appropriate. This heat storage material is used not only for air conditioning heat storage devices for cooling and heating purposes.

It can be used in all fields that utilize heat storage.

Claims (1)

[Claims] (11CHsCOOH (acetic acid) and HOCH2COOH (
A heat storage material characterized by being made of (glycolic acid). @) Hoe) The content ratio of 12COOH is CH3CO
The heat storage material according to claim 1, characterized in that the amount of s s wt % or less (excluding 0 wt %) with respect to the total amount with 0H.