JP2018070801A - Synthetic resin, sealing resin, and resin material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel synthetic resin using a silane-modified polyolefin.SOLUTION: A synthetic resin has a structure represented by the formula (I) (in formula (I), X and Y independently represent a polyolefin main chain that may have a substituent, Rs independently represent a hydrogen atom, an alkyl group, or a polyolefin chain that may have a substituent).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a novel synthetic resin using a silane-modified polyolefin. The present invention also relates to an encapsulating resin containing the synthetic resin and a resin material containing the encapsulating resin.

  Conventionally, polyolefin, which is a general-purpose resin, has been used as various materials in a wide range of fields because it is inexpensive and has excellent mechanical properties. Furthermore, various modifications have been made by chemically modifying polyolefins. For example, silane-modified polyolefin has improved mechanical properties and flame retardancy by silanol groups in the polymer reacting as moisture after molding and cross-linking via -C-Si-O-Si-C- bonds Therefore, it is used in various fields such as an insulating coating material for electric wires, a pipe material, and a battery sealing material (for example, Patent Document 1). To date, there is still a demand for the development of resins with various performances.

JP 2000-212291 A

  The present invention has been made in view of the above-mentioned background art, and an object thereof is to provide a novel synthetic resin using a silane-modified polyolefin.

  As a result of intensive studies to solve the above problems, the present inventors have developed a novel synthetic resin having a specific structure using a silane-modified polyolefin, and have completed the present invention.

That is, according to one aspect of the present invention,
The following formula (I):
(In the formula (I), X and Y are each independently a polyolefin main chain which may have a substituent, and each R independently represents a hydrogen atom, an alkyl group, or a substituent. And a synthetic resin having a structure represented by the following formula:

  According to another aspect of the present invention, there is provided a synthetic resin, which is a reaction product obtained by crosslinking a hydroxyl group-containing polyolefin and a silane-modified polyolefin through a siloxane bond.

  In the aspect of the present invention, the hydroxyl group-containing polyolefin preferably contains an ethylene-vinyl alcohol copolymer.

  In the aspect of the present invention, the silane-modified polyolefin preferably contains silane-modified polyethylene.

  According to another aspect of the present invention, there is provided an encapsulating resin for controlling the release of an encapsulated material, the encapsulating resin including the above synthetic resin.

  According to another aspect of the present invention, there is provided a resin material including an encapsulating material and the encapsulating resin, wherein the encapsulating material is dispersed in the encapsulating resin.

  In an aspect of the present invention, it is preferable to form a sea-island structure having an island part of the encapsulating material and a sea part of the encapsulating resin.

  In the aspect of the present invention, it is preferable that a siloxane bond of the sealing resin in the sea part exists on the outer peripheral part of the island part.

  In the aspect of the present invention, the encapsulating material is preferably a core-shell structure.

  In the aspect of the present invention, the encapsulated material is preferably selected from heat storage materials.

  According to the present invention, a novel synthetic resin using a silane-modified polyolefin is provided. The synthetic resin can be suitably used as an encapsulating resin for controlling the release of the encapsulated material.

It is the figure which compared the 29Si-solid state NMR spectrum of the silane modified LLDPE used in Example 1, and a synthetic resin. It is a transmission electron microscope (TEM) image of the cross section of the thermal storage resin material of Example 2 (magnification 10,000 times). It is a transmission electron microscope (TEM) image of the island part of the cross section of the thermal storage resin material of Example 2 (magnification 100,000 times).

<Synthetic resin>
The synthetic resin of the present invention includes the following (I):
(In the formula (I), X and Y are each independently a polyolefin main chain optionally having a substituent such as a hydroxyl group or an alkyl group, and each R is independently a hydrogen atom or an alkyl group. Or a polyolefin chain which may have a substituent such as a hydroxyl group or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group.)
It has the structure represented by these. In particular, in formula (I), X may be a polyolefin main chain having a hydroxyl group in the side chain as a substituent. Y may be a polyolefin main chain having an alkyl group as a substituent in the side chain, and may form a crosslinked structure with another polyolefin main chain via the substituent. The synthetic resin having such a structure can be suitably used as an encapsulating resin for controlling the release of the encapsulated material.
Without being bound by theory, by dispersing the encapsulated material in the synthetic resin, the siloxane bond in the synthetic resin plays a role as a phase for encapsulating the encapsulated material, and the encapsulated material is released. It is estimated that control is possible.

The synthetic resin of the present invention has the following formula (II):
(In formula (II), m: n = 10-80: 90-20, o: p = 99.5-90: 0.5-10, preferably m: n = 20-70: 80. -30, o: p = 99-95: 1-5, each R is the same as R in formula (I), each independently a hydrogen atom or an alkyl group, and each R Each independently represents a hydrogen atom, an alkyl group, an alkylene group, or an aryl group.)
It preferably has a structure represented by In the formula (II), each R ′ may partially have an alkyl group, and may form a crosslinked structure with another polyolefin main chain via each R ′. By using the synthetic resin having such a structure as the encapsulating resin, the release of the encapsulated material can be further controlled.

According to another aspect, the synthetic resin of the present invention is a reaction product in which a hydroxyl group-containing polyolefin and a silane-modified polyolefin are cross-linked via a siloxane bond. A synthetic resin of two types of polyolefin integrated through a siloxane bond is obtained by a silane coupling reaction between the hydroxyl group of the hydroxyl group-containing polyolefin and the silanol group of the silane-modified polyolefin. Such a synthetic resin can be suitably used as an encapsulating resin for controlling the release of the encapsulated material.
Without being bound by theory, by dispersing the encapsulated material in the synthetic resin, the siloxane bond in the synthetic resin plays a role as a phase for encapsulating the encapsulated material, and the encapsulated material is released. It is estimated that control is possible.

The hydroxyl group-containing polyolefin only needs to have a hydroxyl group in the side chain of the polyolefin main chain, and may have a substituent other than the hydroxyl group in the side chain. Moreover, the silane modified polyolefin should just have the substituent (Y-Si- (OR) ₃ ) which becomes silanol by hydrolysis in the side chain of the polyolefin main chain. Furthermore, the silane-modified polyolefin may have a substituent other than the substituent that becomes silanol by hydrolysis in the side chain, and examples thereof include an alkyl group, an alkylene group, and an aryl group, preferably 1 carbon atom. ˜6 alkyl groups. Such a synthetic resin has a structure represented by the above (I).

  Examples of the polyolefin of the hydroxyl group-containing polyolefin and the silane-modified polyolefin include polyethylene, polypropylene, polybutylene, and modified resins thereof. One or more of these may be used in combination. Of these polyolefins, polyethylene is preferred. For example, high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE) can be appropriately selected as the polyethylene according to the purpose.

  As the hydroxyl group-containing polyolefin used for the synthetic resin, an ethylene-vinyl alcohol copolymer (polyethylene having a hydroxyl group in the side chain) is preferably used. The ethylene-vinyl alcohol copolymer has a vinyl alcohol content (hydroxyl group content) of preferably 20 to 90 mol%, more preferably 30 to 80 mol%, and more preferably 50 to 80 mol%. More preferably. Moreover, it is preferable to use silane-modified polyethylene as the silane-modified polyolefin. The synthetic resin in such a combination has a structure represented by the above formula (II).

  The content of the hydroxyl group-containing polyolefin and silane-modified polyolefin used in the production of the synthetic resin in the entire resin is preferably 1 to 99:99 to 1, more preferably 5 to 95:95 to 5. When the content ratio is about the above range, the silane coupling reaction of the hydroxyl group-containing polyolefin and the silane-modified polyolefin sufficiently proceeds to obtain the desired synthetic resin of the present invention, and the by-product (the silane-modified polyolefin is bonded to each other). (Resin etc.) can be suppressed.

  In the present invention, the method for producing the synthetic resin is not particularly limited, and the hydroxyl group of the hydroxyl group-containing polyolefin and the silanol group of the silane-modified polyolefin can be synthesized by a conventionally known silane coupling reaction. The reaction conditions can be appropriately selected from conventionally known conditions in consideration of the hydroxyl group of the hydroxyl group-containing polyolefin to be used and the melting temperature of the silane-modified polyolefin.

  The production of the synthetic resin of the present invention in the obtained reaction product can be confirmed as follows. Specifically, the generation of siloxane bonds (—C—Si—O—C—) in the synthetic resin can be confirmed by the spectrum of 29Si-solid NMR analysis of the reaction product. Moreover, if there is no production | generation of the coupling | bonding (-C-Si-O-Si-C-) of silane modification polyolefin by the spectrum of the 29Si-solid NMR analysis of a reaction product, the resin which the silane modification polyolefin couple | bonded will produce | generate. You can confirm that you are not doing. By the method as described above, the synthesis of the synthetic resin in which the hydroxyl group-containing polyolefin and the silane-modified polyolefin are integrated can be demonstrated.

<Resin for encapsulation>
The encapsulating resin of the present invention contains the above synthetic resin, and is suitably used as a resin for controlling the release of the encapsulated material. The encapsulating resin may contain a resin other than the synthetic resin as long as the performance is not impaired. The encapsulating resin and the other resin may be integrated by crosslinking, or the other resin may be dispersed in the encapsulating resin without being crosslinked.

  Examples of the other resin include polyolefin resin, polyester resin, acrylic resin, urethane resin, epoxy resin, polycarbonate resin, cellulose resin, acetal resin, vinyl resin, polystyrene resin, polyamide resin, polyimide resin, melamine resin, phenol resin, Examples thereof include silicone resins, fluororesins, and resins obtained by modifying these resins.

  The content of the synthetic resin in the encapsulating resin is preferably 50% or more, more preferably 70% or more, and further preferably 90% or more and 100% or less. If the content of the synthetic resin is about the above range, the performance as the encapsulating resin can be sufficiently exhibited.

<Resin material>
The resin material of the present invention includes an encapsulating material and the encapsulating resin, and the encapsulating material is dispersed in the encapsulating resin. In a dispersed state in the resin material, it is preferable that a sea-island structure having an island part of the encapsulated material and a sea part of the synthetic resin is formed, and the siloxane bond of the sea part synthetic resin is formed on the outer peripheral part of the island part. More preferably it is present. By forming such a sea-island structure, the synthetic resin in the sea part can enclose (hold) the encapsulated material in the island part, and suppress the release of the encapsulated material from the synthetic resin over a long period of time. it can. In particular, it is presumed that the release of the encapsulated material in the island part can be further suppressed by the siloxane bonds of the synthetic resin in the sea part being concentrated on the outer peripheral part of the island part.

  The kind of the material to be encapsulated is not particularly limited, and various substances can be encapsulated in the resin material. For example, the material to be encapsulated is preferably in the form of fine particles such as a core-shell structure or a microcapsule from the viewpoint of easy encapsulation in a resin material. The average particle diameter of the fine particles is preferably 10 to 500 nm, more preferably 40 to 200 nm. The average particle size of the core-shell structure can be measured from small angle X-ray scattering (SAXS).

  The encapsulated material may be any material that is encapsulated in a resin material for the purpose of release control, and includes a heat storage material. In particular, as the encapsulated material, a heat storage material for the purpose of suppressing the release of the encapsulated material over a long period of time can be suitably used. Further, as the encapsulating material, a fragrance or the like for the purpose of gradual release of the encapsulating material over a long period of time can be suitably used.

  The resin material of the present invention can be molded by a known method such as an extrusion molding method, an injection molding method, a calendar molding method, a blow molding method, or a compression molding method. Various shapes, such as a film form and a granular form, may be sufficient as the molded object of the resin material.

<Heat storage resin material>
As an example of the resin material of the present invention, a heat storage resin material using a heat storage material as an encapsulated material will be described in detail. The heat storage resin material includes the following thermoplastic elastomer, the following paraffinic hydrocarbon, and the above synthetic resin. In a heat storage resin material, paraffinic hydrocarbons are used as cores, and the core-shell structure with the thermoplastic elastomer as a shell is enclosed (held) in the synthetic resin, thereby suppressing paraffinic hydrocarbon bleeding. Can do. Hereinafter, each component of the heat storage resin material will be described in detail.

[Thermoplastic elastomer]
The thermoplastic elastomer used in the present invention has a hard segment block (polystyrene block) which is a crystal structure having styrene as a repeating unit, and has an amorphous structure due to the presence of branches derived from a conjugated diene compound even after hydrogenation treatment. It is preferable to further have a soft segment block (branched polyolefin 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 thermoplastic elastomer may further have a hard segment block other than the polystyrene block.

  In thermoplastic elastomers, polystyrene blocks are pseudo-crosslinked to form spherical colloidal particles. It is estimated that gaps are formed between the soft segments due to the aggregation of the formed spherical colloidal particles, and the following paraffinic hydrocarbons are finely dispersed in the gaps. When a thermoplastic elastomer has only one polystyrene block in the molecule, the space in which the paraffinic hydrocarbon can be dispersed is large. Therefore, compared to the thermoplastic elastomer having two polystyrene blocks in the molecule, the paraffinic hydrocarbon Can be stably supported, and bleeding of paraffinic hydrocarbons can be further suppressed. In addition, polyethylene-poly (ethylene / butylene) -polyethylene block copolymer (CEBC) that does not have a polystyrene block as a hard segment is presumed to form a pseudo-crosslink of a crystalline polyethylene block. It is presumed to be weaker than the pseudo-crosslinking and inferior in carrying performance of the heat storage material.

  Examples of the thermoplastic elastomer having only one polystyrene block in the molecule include a diblock body having one polystyrene block as a hard segment block and one branched polyolefin block as a soft segment block. Examples of such a diblock body include a polystyrene-poly (ethylene / propylene) block copolymer (hereinafter sometimes abbreviated as “SEP”) and a polystyrene-poly (ethylene / butylene) block copolymer (hereinafter, “ SEB ”), polystyrene-polyisobutylene copolymer (hereinafter sometimes abbreviated as“ SIB ”), and the like. Among these diblock bodies, polystyrene-poly (ethylene / propylene) block copolymers are preferable. Examples of polystyrene-poly (ethylene / propylene) block copolymers are those sold by Kraton Polymer Japan Co., Ltd. under the trade names of Kraton (registered trademark) G (SEP type), “1701EU”, and “1702HU”. Is exemplified.

  The thermoplastic elastomer preferably does not contain a polyethylene block as a soft segment block. When using a paraffinic hydrocarbon, if it has a polyethylene block in the molecule, the paraffinic hydrocarbon adsorbs on the polyethylene block, which may reduce the amount of heat stored when used as a heat storage material. From the viewpoint of having a high heat storage amount and suppressing bleeding, the thermoplastic elastomer can be suitably used as a diblock body having only one polystyrene block in the molecule and no polyethylene block.

  The thermoplastic elastomer containing a diblock copolymer having a polystyrene block and a branched polyolefin block preferably has a melting peak derived from a hard segment when measured by a differential scanning calorimetry (DSC method). More preferably, it has a melting peak in the range of ˜120 ° C.

  A thermoplastic elastomer can be used alone or in combination of two or more. In the case of using a mixture of two or more, it is preferable that at least a polystyrene-poly (ethylene / propylene) block copolymer is included.

[Paraffinic hydrocarbons]
The paraffinic hydrocarbon used in the present invention is preferably an n-paraffin having 12 to 50 carbon atoms and having a phase transition temperature of -20 ° C to 100 ° C. These n-paraffins are usually obtained from a petroleum fraction by rectification. Due to the limitations of the refining technique, each carbon number n-paraffin may contain several mass% of adjacent carbon number n-paraffins. In addition, although what was synthesize | combined may be used for n-paraffin, it is simple and cheap to use the thing 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.

  Paraffinic hydrocarbons useful as a latent heat storage material are n-paraffins having a carbon number of 12 or more and 20 or less and having a phase transition temperature in the range of −10 ° C. to 35 ° C. in the range of cold insulation to residential environment temperature. Specifically, it is preferable to use n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, and n-eicosane. Particularly preferred as the latent heat storage material is a material mainly containing n-tetradecane, n-hexadecane, n-octadecane, and n-eicosane having a large amount of latent heat of phase transition and an even number of carbon atoms.

<Method for producing resin material>
An example of the method for producing the resin material of the present invention will be described. When the heat storage material is used as the encapsulated material, the resin material (heat storage resin material) is kneaded by mechanical means with the thermoplastic elastomer and the paraffinic hydrocarbon as the heat storage material, and the synthetic resin, Preferably, it can be obtained by melt-kneading (kneading step).

As a kneading | mixing process, a thermal storage resin material can be manufactured in the following procedure, for example with a biaxial extrusion kneader. In the first step, a thermoplastic elastomer and paraffinic hydrocarbon are melt-kneaded. In this step, a core-shell structure having a paraffinic hydrocarbon as a core and a thermoplastic elastomer as a shell is formed.
In the second step, melt-kneading is performed by simultaneously adding a hydroxyl group-containing polyolefin and a silane-modified polyolefin, which are components of the synthetic resin, and a crosslinking catalyst. In this step, it is presumed that a sea-island structure having an island part of the core-shell structure and a sea part composed of a hydroxyl group-containing polyolefin and a silane-modified polyolefin is formed.
At that time, a silanol group generated by hydrolysis of the silane-modified polyolefin and a hydroxyl group of the hydroxyl group-containing polyolefin undergo a silane coupling reaction to form a synthetic resin. In this step, it is presumed that the siloxane bond of the synthetic resin gathers on the outer periphery of the island portion and encloses (holds) the core-shell structure in the island portion.

  The cross-linking catalyst is a catalyst for efficiently causing a silane coupling reaction between a hydroxyl group-containing polyolefin and a silane-modified polyolefin. Examples of the crosslinking catalyst include metal carboxylates such as tin, zinc, iron, lead, and cobalt, titanate esters, organic bases, inorganic acids, and organic acids. Specific examples include dibutyltin dilaurate, dibutyltin dimaleate, dibutyltin mercaptide and the like. In addition, this cross-linking catalyst has an advantage that it becomes easy to add and control mixing during kneading by preparing a master batch by a method of kneading with a polyolefin to be used in advance.

  The melt-kneading is preferably performed at a temperature at which the mixture of the thermoplastic elastomer, the paraffinic hydrocarbon, the hydroxyl group-containing polyolefin, and the silane-modified polyolefin is melted, and can be performed, for example, at about 150 to 200 ° C. Any mixing means can be used as long as the mixing is performed by mechanical means. Examples of the mixing means include stirring, mixing, and kneading. Examples of the device having the function include a stirrer, a mixer, and a kneading machine. Moreover, the two-roll used for rubber | gum processing or thermoplastic resin processing, a Banbury mixer, an extruder, a biaxial kneading extruder, etc. are mentioned. In addition, you may add the additive etc. which are generally used for melt-kneading to a mixture.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is limited to the following Example and is not interpreted.

  Each chemical used in the examples and comparative examples was obtained from the market without purification. Hereinafter, the hydroxyl group-containing polyolefin and the silane-modified polyolefin, the thermoplastic elastomer, the paraffinic hydrocarbon, and the thermoplastic resin, which are the raw materials of the synthetic resin used in Examples and Comparative Examples, are shown.

<Hydroxyl-containing polyolefin>
Ethylene-vinyl alcohol copolymer (Kuraray Co., Ltd., OH ratio 52%, trade name: EVAL G grade)
Ethylene-vinyl alcohol copolymer (manufactured by Kuraray Co., Ltd., OH ratio 62%, trade name: EVAL H grade)
Ethylene-vinyl alcohol copolymer (manufactured by Kuraray Co., Ltd., OH ratio 73%, trade name: EVAL L grade)
<Silane modified polyolefin>
Silane modified LLDPE (Mitsubishi Chemical Co., Ltd., trade name: Linkron XLE830N)
Silane modified HDPE (Mitsubishi Chemical Co., Ltd., trade name: Linkron XHE740N)
<Crosslinking catalyst>
Master batch of silanol condensation catalyst (Mitsubishi Chemical Corporation, trade name: HZ082)
<Thermoplastic resin>
Homo polypropylene pellets (PP, manufactured by Sun Allomer, trade name: PL400A)
<Thermoplastic elastomer>
Polystyrene-poly (ethylene / propylene) block copolymer (“SEP”, manufactured by Kraton Polymer Japan, trade name: Kraton G1701EU)
<Paraffinic hydrocarbon>
n-Heptadecane (C17) (manufactured by JX Energy, trade name: TS-7)

<Manufacture of synthetic resin>
[Example 1]
6 parts by mass of an ethylene-vinyl alcohol copolymer (EVAL G grade), 24 parts by mass of silane-modified LLDPE, and 1.1 parts by mass of a crosslinking catalyst are simultaneously charged into a kneading extruder and melt kneaded at 160 ° C. for 30 minutes. Thus, a synthetic resin in which an ethylene-vinyl alcohol copolymer and a silane-modified LLDPE were subjected to a silane coupling reaction was obtained.

<Measurement of synthetic resin>
The binding / reaction state of the synthetic resin obtained in Example 1 was confirmed.
<29Si-solid NMR>
The 29Si-solid NMR measurement of the synthetic resin and the raw material silane-modified LLDPE was performed, and the obtained spectrum is shown in FIG. In the spectrum of the silane-modified LLDPE in FIG. 1 (upper side), a peak derived from —C—Si (OR) ₃ group was confirmed, but in the spectrum of the synthetic resin (lower side), it was derived from Si (OR) ₃ . Instead of reducing the peak, the generation of a peak derived from the —C—Si—O—C— group was confirmed. That is, according to the spectrum of the synthetic resin, the —C—Si (OR) ₃ group of the silane-modified LLDPE reacted to form the synthetic resin. Moreover, the production | generation of -C-Si-O-Si-C- group was not confirmed, but it was confirmed that the resin which silane modified LLDPE couple | bonded is not produced | generated.

<Manufacture of heat storage resin material>
[Example 2]
20 parts by mass of a polystyrene-poly (ethylene / propylene) block copolymer (SEP) and 50 parts by mass of n-heptadecane (TS-7) are charged into a kneading extruder and melt-kneaded to form n-heptadecane as a core. Then, a core-shell type structure having a polystyrene-poly (ethylene / propylene) block copolymer as a shell was formed. Subsequently, 6 parts by mass of an ethylene-vinyl alcohol copolymer (EVAL G grade), 24 parts by mass of silane-modified LLDPE, and 1.1 parts by mass of a crosslinking catalyst were simultaneously added, and then melt-kneaded to perform a silane coupling reaction. Resin was formed to obtain a heat storage resin material pellet in which the core-shell structure was dispersed in the synthetic resin.

  The synthetic resin in the heat storage resin material pellet obtained in Example 2 was sampled, and the binding / reaction state of the synthetic resin was confirmed in the same manner as in Example 1. As a result, it was confirmed that a synthetic resin in which the silane-modified LLDPE and the ethylene-vinyl alcohol copolymer were integrated via a siloxane bond (—C—Si—O—C— group) was confirmed.

[Example 3]
A heat storage resin material pellet was obtained in the same manner as in Example 2 except that the type of the ethylene-vinyl alcohol copolymer was changed from G grade to H grade.

[Example 4]
Thermal storage resin pellets were obtained in the same manner as in Example 2 except that the type of ethylene-vinyl alcohol copolymer was changed from G grade to L grade.

[Example 5]
A heat storage resin material pellet was obtained in the same manner as in Example 2 except that the silane-modified LLDPE was changed to silane-modified HDPE.

[Example 6]
A heat storage resin material pellet was obtained in the same manner as in Example 3 except that the silane-modified LLDPE was changed to silane-modified HDPE.

[Example 7]
A heat storage resin material pellet was obtained in the same manner as in Example 4 except that the silane-modified LLDPE was changed to silane-modified HDPE.

[Comparative Example 1]
20 parts by mass of polystyrene-poly (ethylene / propylene) block copolymer (SEP), 50 parts by mass of n-heptadecane (TS-7) and 30 parts by mass of homopolypropylene pellets are charged into a kneading extruder and melt-kneaded. Then, a core-shell type structure having n-heptadecane as a core and a polystyrene-poly (ethylene / propylene) block copolymer as a shell is formed, and the core-shell type structure is dispersed in a homopolypropylene resin. Pellets were obtained.

<Performance evaluation of encapsulating resin>
[Initial bleed]
For the heat storage resin pellets obtained in Examples 2 to 7 and Comparative Example 1, the amount of paraffinic hydrocarbons bleed on the surface immediately after production was measured by the following method.
After putting 1 g of the heat storage resin material pellets obtained in each Example and Comparative Example into each sample bottle, 50 g of ethylene glycol was added, and left in a dryer at 50 ° C. for 1 hour. Thereafter, the amount of paraffinic hydrocarbon dissolved in the ethylene glycol solution was measured by gas chromatography. The measurement results are shown in Table 1.
From the results of Examples 2 to 7 and Comparative Example 1, the heat storage resin material pellets of Examples 2 to 7 were not bleed at all in the initial state, and the heat storage resin material pellets of Comparative Example 1 were bleed even in the initial state. Was. Therefore, it was found that the synthetic resin of the present invention is superior in bleed resistance and superior in performance as an encapsulating resin as compared with polypropylene resin.

[Long-term bleed]
For the heat storage resin pellets obtained in Examples 2 to 7 and Comparative Example 1, the amount of paraffinic hydrocarbons bleed on the surface after the phase change cycle test was measured by the following method.
1 g of the heat storage resin material pellets obtained in each of the examples and comparative examples is put in each sample bottle and left in a constant temperature and humidity chamber that sequentially changes at 15 ° C. to 25 ° C. Repeated. After each sample bottle was taken out, 50 g of ethylene glycol was added and left in a dryer at 50 ° C. for 1 hour. Thereafter, the amount of paraffinic hydrocarbon dissolved in the ethylene glycol solution was measured by gas chromatography. As for the number of phase change cycles, Example 2 was 19 cycles and 99 cycles, and Examples 3 to 7 and Comparative Example 1 were 27 cycles and 84 cycles. The measurement results are shown in Table 1.
From the results of Examples 2 to 7 and Comparative Example 1, the heat storage resin material pellets of Examples 2 to 7 had no bleed even after a long-term phase change cycle test, and the heat storage resin material pellets of Comparative Example 1 No bleeding occurred after a long-term phase change cycle test. Therefore, it was found that the synthetic resin of the present invention is superior in long-term bleed resistance and superior in performance as an encapsulating resin compared to polypropylene resin.

<Measurement and evaluation of heat storage resin pellets>
<TEM observation>
Using an ultramicrotome (Leica ULTRACUT-S), an ultrathin section of the heat storage resin material pellet obtained in Example 2 was prepared, and the cross section was taken as a transmission electron microscope (TEM, transmission electron microscope H-800 manufactured by Hitachi, Ltd.). ). The observed TEM image (magnification 10,000 times) is shown in FIG. Moreover, the TEM image (magnification 100,000 times) which expanded the island part was shown in FIG. From the result of FIG. 2, it was found that the sea part of the synthetic resin and the island part of the core-shell structure were dispersed in an independent state. In particular, according to FIG. 3, it was found that the core-shell structure is concentrated on the island. Further, from the mapping analysis of Si atoms and O atoms in the central part (in the white square frame) of FIG. 2, it was confirmed that an outline in which Si atoms and O atoms concentrate on the outer peripheral part of the island part was confirmed. .

<Gel fraction>
About the heat storage resin material pellet obtained in Examples 2-7 and Comparative Example 1, the gel fraction was measured. That is, 1 g of the heat storage resin material pellet was weighed and placed in a Soxhlet extractor, and heated and refluxed with 300 ml of xylene for 3 hours. Thereafter, the pellets were taken out, dried in a dryer at 140 ° C. for 1 hour, and allowed to cool to room temperature. Then, the weight was precisely weighed, and the mass percentage with respect to the mass before the test was taken as the gel fraction. The measurement results are shown in Table 1.
When both the polyolefin resins as raw materials have reacted, the theoretical value of the gel fraction is 30%. Since the gel fraction of the heat storage resin pellets obtained in Examples 2 to 7 was 19% to 28%, it was found that most of both polyolefin resins as raw materials reacted to form a synthetic resin. .

<Supercooling degree>
About the heat storage resin material pellet obtained in Examples 2-7 and Comparative Example 1, the freezing point (° C) and the melting point (° C) were measured using a differential calorimeter (Hitachi High-Tech Science Co., Ltd., DSC7000X type). “Melting point (° C.) − Freezing point (° C.)” was defined as the degree of supercooling (° C.). The measurement results are shown in Table 1. From the results of Examples 2 to 7, it was found that the heat storage resin material pellet has a small supercooling value and is excellent in performance as a heat storage body. That is, it was found that the encapsulating resin containing the synthetic resin of the present invention does not hinder the performance of the heat storage material that is the encapsulated material.

Claims (10)

The following formula (I):
(In the formula (I), X and Y are each independently a polyolefin main chain which may have a substituent, and each R independently represents a hydrogen atom, an alkyl group, or a substituent. It is a polyolefin chain that may have.)
A synthetic resin having a structure represented by:   A synthetic resin, which is a reaction product obtained by crosslinking a hydroxyl group-containing polyolefin and a silane-modified polyolefin via a siloxane bond.   The synthetic resin according to claim 2, wherein the hydroxyl group-containing polyolefin contains an ethylene-vinyl alcohol copolymer.   The synthetic resin according to claim 2 or 3, wherein the silane-modified polyolefin contains silane-modified polyethylene.   An encapsulating resin for controlling the release of an encapsulated material, the encapsulating resin comprising the synthetic resin according to claim 1. Encapsulating material;
An encapsulating resin according to claim 5;
A resin material in which the encapsulating material is dispersed in the encapsulating resin.   The resin material of Claim 6 which forms the sea island structure which has the island part of the said to-be-enclosed material, and the sea part of the said resin for encapsulation.   The resin material according to claim 7, wherein a siloxane bond of the encapsulating resin in the sea portion exists in an outer peripheral portion of the island portion.   The resin material according to any one of claims 6 to 8, wherein the encapsulating material is a core-shell structure.   The resin material according to any one of claims 6 to 9, wherein the encapsulating material is made of a heat storage material.