JP5522513B2 - Shape memory resin composition, shape memory resin molded body, and method of manufacturing shape memory resin molded body - Google Patents

Description

  The present invention relates to a shape memory resin composition, a shape memory resin molded body, and a method for producing a shape memory resin molded body.

  The shape memory material is deformed at a predetermined temperature or higher. When the deformed shape memory material is cooled, the deformed shape is fixed. If the shape memory material is heated again, the shape before deformation is restored. As such shape memory materials, shape memory alloys and shape memory resins are known. Shape memory alloys are used for pipe joints and orthodontics. Shape memory resins are used in heat-shrinkable tubes, fastening pins, laminate materials, medical instruments such as gibbs, and the like. Shape memory resin has advantages such as excellent formability, high shape recovery rate, light weight, free coloring, and low cost compared to shape memory alloys. Expansion is expected.

  The shape memory resin will be described. FIG. 1 is a diagram showing a mechanism for storing the shape of the shape memory resin.

  When the shape memory resin composition is heated, melted, and solidified for molding, a shape memory resin molded body as shown in FIG. 1A is obtained. FIG. 1B is an enlarged view showing a part of FIG. The shape memory resin molded body has a stationary phase and a reversible phase, and the stationary phases are connected by a reversible phase. The stationary phase is a portion in which movement is restricted by a physical bond or a chemical bond (cross-linking point), and is a portion that is not easily deformed. The reversible phase is a portion that can move more freely than the stationary phase, and is a portion that becomes fluid at a temperature equal to or higher than the softening temperature T1. In such a shape memory resin molded product, the initial shape (original shape) is stored.

  In order to deform the shape memory resin molded body into a desired shape, the stationary phase is not melted but heated so that only the reversible phase is melted. Thereby, as FIG.1 (c) shows, only a reversible phase will be in a fluid state and a shape memory resin molded object will soften. When an external force is applied to the softened shape memory resin molded body, it can be deformed into a desired shape as shown in FIG. When the deformed shape memory resin molded body is cooled to a solidification temperature T2 or lower, the reversible phase is solidified and the deformed shape is fixed as shown in FIG.

  In the shape memory resin molded body in which the shape after deformation is fixed, the shape is maintained by the reversible phase temporarily fixed. Therefore, if the temperature is again heated to a temperature equal to or higher than the softening temperature T1, the reversible phase exhibits rubbery characteristics and becomes stable. As a result, the initial shape is restored as shown in FIG. Thereafter, by cooling to a solidification temperature T2 or lower, the reversible phase is cured and a shape memory resin molded body having an initial shape is obtained.

  As a related technique, there is a shape memory resin described in Patent Document 1 (Japanese Patent Laid-Open No. 2008-121024). This publication discloses a shape memory resin having a three-dimensional structure in which a crystalline resin having a plurality of functional groups serving as crosslinking sites and having a number average molecular weight of 500 or more and 3000 or less is crosslinked and having a crystal melting temperature (Tm). There is disclosed a shape memory resin characterized by being 60 ° C. or higher and a crystallization temperature (Tc) of 45 ° C.

  As another related technique, there is a shape memory resin described in Patent Document 2 (Japanese Patent Laid-Open No. 2009-96885). In this publication, a crystalline resin having a plurality of functional groups serving as crosslinking sites and having a number average molecular weight of 2000 or more and 30000 or less, a polyfunctional compound having a functional group of the same type as the functional group of the crystalline resin, and a linker There is disclosed a shape memory resin having a three-dimensional structure cross-linked by using a crystal melting temperature (Tm) of 60 ° C. or higher and a crystallization temperature (Tc) of 45 ° C. or lower.

  As another related technique, there is a shape memory resin material described in Patent Document 3 (Japanese Patent Laid-Open No. 63-179955). This publication includes (A) 97 to 30% by weight of a crystalline block copolymer and (B) 3 to 70% by weight of a low melting crystalline polymer having a melting point in the temperature range of 25 ° C to 150 ° C. The shape memory resin material is maintained.

  As another related technique, there is a shape memory polymer semi-cured material described in Patent Document 4 (Japanese Patent Application Laid-Open No. 2004-300292). This publication discloses a difunctional, trifunctional, or bifunctional and trifunctional isocyanate, a polyol, and a bifunctional chain extender containing an active hydrogen group in a molar ratio of functional groups: isocyanate: polyol: chain extension. A shape memory polymer semi-cured material comprising a matrix resin composition containing an agent = 5.0 to 1.0: 1.0: 4.0 to 0 is disclosed.

JP 2008-121024 A JP 2009-96885 A JP-A 63-179955 JP 2004-3000292 A

  When a material having a high softening temperature T1 is used as the shape memory resin molding, the solidification temperature T2 tends to be high. When the softening temperature T1 and the solidification temperature T2 are low, the deformation operation can be performed at a low temperature. However, if the softening temperature T1 is low, even if the softening temperature T1 is not intended to be deformed, the softening temperature T1 is likely to be deformed due to the temperature rise. That is, the shape memory resin molded body having a low softening temperature T1 has low heat resistance. Conversely, a shape memory resin molded body having a high softening temperature T1 has high heat resistance. However, if the softening temperature T1 is high, the solidification temperature T2 tends to be high. The deformation operation needs to be performed at a temperature equal to or higher than the solidification temperature T2. It is necessary to handle the shape memory resin molded body at a high temperature, and special considerations are necessary in terms of safety.

  If a shape memory resin molded body having a high softening temperature T1 and a low solidification temperature T2 is used, the heat resistance can be increased, and it can be easily handled even during deformation. However, no such shape memory resin molding has been reported so far.

  The shape memory resin composition according to the present invention has a crystalline resin component having a plurality of cross-linking functional groups to be cross-linked sites in the molecule, and the crystalline resin component by binding to the plurality of cross-linking reactive groups. Contains a linker to be crosslinked and an additive. Each of the plurality of cross-linking functional groups has a hydrogen donor or hydrogen acceptor in a hydrogen bond. The additive has a hydrogen acceptor or a hydrogen donor in a hydrogen bond so that a hydrogen bond can be formed with each of the cross-linking functional groups.

  The shape memory resin molded body according to the present invention is obtained by crosslinking the crystalline resin component of the above-described shape memory resin composition.

  The method for producing a shape memory resin molded body according to the present invention includes a step of preparing the above-described shape memory resin composition, a step of changing the shape of the shape memory resin composition to a desired shape, and the desired shape. And the step of crosslinking the crystalline resin component via the linker to obtain a molded body.

  According to the present invention, there are provided a shape memory resin composition, a shape memory resin molded body, and a method for manufacturing a shape memory resin molded body, which can improve heat resistance and can be deformed at a low temperature. .

It is a figure which shows the mechanism of the shape memory of a shape memory resin molding.

  Subsequently, an embodiment of the present invention will be described.

  The present inventor has considered using a Tc type shape memory resin as the shape memory resin. The Tc-type shape memory resin has a crystallization temperature Tc and a crystal phase melting temperature (melting temperature Tm). The crystallization temperature Tc is a temperature at which molecular motion is frozen and the resin crystallizes during cooling. The melting temperature Tm is a temperature at which the resin melts due to molecular motion during heating. The Tc-type shape memory resin can be deformed when heated to the melting temperature Tm or higher. When the heated Tc type shape memory resin is cooled below the crystallization temperature Tc, the shape is fixed. That is, the melting temperature Tm can be regarded as the softening temperature T1, and the crystallization temperature Tc can be regarded as the solidification temperature T2. For crystallization to occur, the molecules must be oriented. A resin having a large molecular size makes it difficult to orient the molecules. Therefore, the crystallization temperature Tc is somewhat lower than the melting temperature Tm.

  The inventor has considered increasing the difference between the crystallization temperature Tc and the melting temperature Tm. That is, it was considered to use a shape memory resin having a high melting temperature Tm and a low crystallization temperature Tc. By increasing the melting temperature Tm, the heat resistance can be increased. On the other hand, by lowering the crystallization temperature Tc, a deformation operation can be performed even in a low temperature region. Both heat resistance and operability can be achieved.

  As a result of intensive studies, the present inventor has found that by using hydrogen bonding, only the crystallization temperature Tc can be greatly reduced without significantly reducing the melting temperature Tm. And I thought about using this. That is, the shape memory resin composition according to this embodiment is a resin composition containing a crystalline resin component (A), a linker (B), and an additive (C). The crystalline resin component (A) has a plurality of cross-linking functional groups serving as cross-linking sites in the molecule. The linker (B) crosslinks the crystalline resin component (A) by binding to the crosslinking reactive group of the crystalline resin component (A). Each of the plurality of crosslinking reactive groups contained in the crystalline resin component (A) has a hydrogen donor or a hydrogen acceptor in a hydrogen bond. The additive (C) has a hydrogen acceptor or a hydrogen donor in a hydrogen bond so that a hydrogen bond can be formed with each cross-linking functional group.

  By using this shape memory resin composition, it is possible to obtain a shape memory resin molded body that can be deformed in a low temperature region despite its high heat resistance. This point will be described below.

  The shape of the above-mentioned shape memory resin composition is adjusted to a desired initial shape. And a crosslinking reaction is advanced. The cross-linking functional group of the crystalline resin component is cross-linked through a linker to form a three-dimensional structure. Thereby, a shape memory resin molding is obtained. In the obtained shape memory resin molding, the cross-linking functional group forms a stationary phase, and the portion other than the cross-linking functional group of the crystalline resin component forms a reversible phase. Here, an additive couple | bonds with a crosslinking functional group by a hydrogen bond, and restrains a bridge | crosslinking part. The crystallization movement of the crystalline resin component is restricted by the steric hindrance of the additive. Thereby, the crystallization temperature Tc can be lowered. However, hydrogen bonds are weak bonds compared to covalent bonds and the like. Therefore, the crystal phase grows gradually even at room temperature and becomes a crystal phase that is as stable as when no additive is added, and the additive does not significantly affect the melting temperature Tm of the crystalline resin component. Therefore, the difference between the melting temperature Tm and the crystallization temperature Tc can be increased. Further, the crystallization speed is slowed by restraining the crystallization movement by the additive. That is, when cooling from a high temperature state to a temperature equal to or lower than the crystallization temperature Tc, a time margin can be provided between the time when the temperature reaches the crystallization temperature Tc and the time when the shape is fixed. In the meantime, a deformation operation can be performed. When this degree is large, Tc and Hc cannot be observed by DSC. That is, it is possible to obtain a shape memory resin molded body that can be deformed in a low temperature region despite its high heat resistance. Further, the crystallization movement of the crystalline resin component is not completely inhibited and proceeds at a slow speed. Therefore, the final crystallinity does not decrease.

(Shape memory resin composition)
Then, each component used for a shape memory resin composition is explained in full detail.

(A); Crystalline resin component The crystalline resin component used in the present embodiment has a plurality of cross-linking functional groups serving as cross-linking sites in one molecule. The crystalline resin component undergoes a crosslinking reaction with a linker at the crosslinking functional group to form a three-dimensional structure. The crosslinking reaction between the crosslinking functional group and the linker may be any of an addition reaction, a condensation reaction, and a copolymerization reaction. In addition, as the crosslinking functional group, a group capable of forming a hydrogen bond with the additive is used. That is, the cross-linking functional group has a hydrogen donor or hydrogen acceptor in hydrogen bonding.

  The number of cross-linking functional groups possessed by the crystalline resin component needs to be such that a three-dimensional structure is formed by a cross-linking reaction via a linker. Although details will be described later, a linker having a functional group that undergoes a crosslinking reaction with a crosslinking functional group contained in the crystalline resin component is used. One of the number of cross-linking functional groups of the crystalline resin component and the number of functional groups of the linker needs to be 3 or more. However, if a crosslinkable functional group that can form a branched structure is used, the number of crosslinkable functional groups of the crystalline resin component and the number of functional groups of the linker may be two or more, respectively. The cross-linking functional group is preferably provided at the end of the main chain of the crystalline resin component.

  Specific examples of the cross-linking functional group contained in the crystalline resin component include hydroxy group, carboxy group, isocyanate group, cyanate group, amino group, imino group, carbamoyl group, succinimino group, and epoxy group. . As the crosslinking functional group, those that form an amide bond or a urethane bond are preferably used. When a polycarboxylic acid, polyisocyanate, or the like is used as the linker (B), it is particularly preferable to use a hydroxy group as a crosslinking functional group contained in the crystalline resin component.

  The crystalline resin component may be any of an artificial synthetic product, a natural product extract, and a product synthesized using a natural product. However, it is preferable to have biodegradability from the viewpoint that environmental destruction can be suppressed during disposal.

  Specific examples of the crystalline resin component include polyesters, polyamides, and polyethers. These are preferable because the bonding force between molecules is moderate, the thermoplasticity is excellent, the viscosity at the time of melting is not significantly increased, and the moldability is good. As such a crystalline resin component, polycondensation products, natural product extracts, derivatives thereof, and modified products thereof can be used. The polycondensation product can be synthesized using monomers, oligomers, polymers, derivatives thereof, and modified products thereof. As the monomer, oligomer, and polymer, those obtained by artificial synthesis may be used, or those obtained from biomass raw materials may be used.

  The polyesters are not particularly limited as long as they are produced by polycondensation of a polyhydric alcohol and a polybasic acid. However, aliphatic polyesters are preferred.

  Examples of the polyhydric alcohol include dihydric alcohols such as ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, and 1,6-hexanediol, glycerin, and trimethylolpropane. , Trivalent alcohols such as trimethylolethane, hexanetriol, castor oil, etc., tetravalent alcohols such as pentaerythritol, methylglycoside, diglycerin, polyglycerins such as triglycerin, tetraglycerin, polypenta such as dipentaerythritol, tripentaerythritol, etc. Mention may be made of at least one alcohol selected from the group consisting of erythritol, cycloalkane polyols such as tetrakis (hydroxymethyl) cyclohexanol, and polyvinyl alcohol. That. In addition, as polyhydric alcohols, sugar alcohols such as adonitol, arabitol, xylitol, sorbitol, mannitol, iditol, tallitol, dulcitol, saccharides such as glucose, mannose glucose, mannose, fructose, sorbose, sucrose, lactose, raffinose, cellulose, and the like Mention may be made of at least one alcohol selected from the group consisting of coconut oil-based polyols. In addition, derivatives and modified products of the listed substances can also be used as the polyhydric alcohol.

  Examples of the polybasic acid include phthalic anhydride, maleic anhydride, succinic acid, fumaric acid, and adipic acid. These derivatives and modified products may also be used. These can be used alone or in combination of two or more.

  As the polyesters, polyhydroxypolybutylene succinate is particularly preferable. If polyhydroxypolybutylene succinate is used, biodegradability can be improved and a shape memory resin molded product having a crystallization temperature Tc in a low temperature region can be obtained.

  When polycarboxylic acid, polyisocyanate, or the like is used as a linker, the polyesters preferably have a hydroxyl group at the terminal. Such polyesters are easy to form a cross-linked bond by an ester bond or a urethane bond with the linker. In order to obtain polyesters having a hydroxy group at the terminal, a method of synthesizing a divalent carboxylic acid and a dihydric alcohol as raw materials can be used. In the case of this method, by setting the molar ratio of the dihydric alcohol / divalent carboxylic acid of the raw material to be used to be greater than 1, it is possible to make all the molecular chain ends into hydroxy groups. It is also possible to obtain polyesters having a hydroxy group at the terminal by transesterification. That is, a dihydric alcohol having hydroxyl groups at both ends is added to polyesters having a terminal carboxyl group. As a result, the ester bond in the molecular chain of the polyester is cleaved while transesterifying with the diol. The terminal of the cut polyester will have a hydroxy group. In particular, a three-dimensional crosslinked structure can be formed by transesterification with a trivalent or higher alcohol. As the trihydric or higher alcohol used for transesterification, specifically, those similar to those exemplified as the polyhydric alcohol described above can be used. For example, by transesterifying ester bonds of hydroxyalkanoates such as polyhydroxybutyrolactone and polyhydroxyvalylate with pentaerythritol, a polyester having a total of four hydroxy groups at the molecular chain ends can be obtained. The transesterification product having a carboxy group at the terminal and the unreacted raw material having a hydroxy group at the terminal produced by transesterification can be easily purified and removed.

  Further, the terminal carbonyl group of a polyester resin such as polyalkanoate is effective in introducing a cross-linking functional group by an esterification reaction. Specifically, a crosslinking functional group can be introduced by an esterification reaction using carbodiimides or the like in addition to acid and alkali. It is also possible to introduce a crosslinking functional group by an esterification reaction after derivatizing the carboxy group into an acid chloride using thionyl chloride or allyl chloride.

  As polyamides that can be used as the crystalline resin component, aliphatic polyamides are preferred. Examples of the aliphatic polyamide include polymers of amino acids such as proteins, polycapramide, polyhexamethylene adipamide, nylon 66, nylon 6, nylon 11, nylon 12, nylon 4, derivatives thereof, and modified products thereof. be able to.

  The polyether that can be used as the crystalline resin component is preferably an aliphatic polyether. Specific examples of the aliphatic polyether include polymers exemplified as the polyhydric alcohol described above.

  When a polycondensate synthesized using a monomer, oligomer, or polymer obtained from a biomass raw material is used as the crystalline resin, polylactic acid (manufactured by Shimadzu Corporation, trade name: Lacty, etc.) is used as the polycondensate. , Polyalphahydroxy acids such as polyglycolic acid, polyomegahydroxyalkanoates such as polyepsilon caprolactone (manufactured by Daicel, trade name: Plaxel, etc.), polyalkylene alkanoates and polybutylene succinates that are polymers of butylene succinate And polyamino acids such as poly-γ-glutamate (manufactured by Ajinomoto Co., Inc., trade name: polyglutamic acid, etc.) can be used.

  Further, when a natural product extract is used as the crystalline resin component, any of plant-derived, animal-derived, and microorganism-derived extracts can be used as the natural product extract. Specifically, starch, amylose, cellulose, cellulose ester, chitin, chitosan, gellan gum, carboxyl group-containing cellulose, carboxyl group-containing starch, polysaccharides such as pectinic acid, alginic acid, and microorganisms are used as natural extracts. And polybetahydroxyhydroxyalkanoates (trade name: Biopol, etc., manufactured by Zeneca) which are polymers of hydroxybutyrate and / or hydroxyvalerate. Of these, starch, amylose, cellulose, cellulose ester, chitin, chitosan, polybutyrate hydroxyalkanoate which is a polymer of hydroxybutyrate and / or hydroxyvalerate synthesized by microorganisms, and the like are preferable.

  As the crystalline resin component, it is preferable to use a resin having a number average molecular weight of 500 or more and 30,000 or less. The number average molecular weight of the crystalline resin component is more preferably 1,000 or more and 20,000 or less, and still more preferably 10,500 or less. When the number average molecular weight of the crystalline resin is 500 or more, a degree of crystallinity can be obtained so that the deformed shape can be fixed satisfactorily. In addition, a shape memory resin molded article having excellent heat resistance is obtained.

  When both terminal hydroxypolybutylene succinate is used as the crystalline resin component, the melting temperature Tm of the shape memory resin molded article can be sufficiently increased if the number average molecular weight is 2,000 or more, and the heat resistance is improved. Can be increased. Further, if the number average molecular weight of the crystalline resin is 10,500 or less, Tc can be made sufficiently low, but operation at a low temperature is somewhat difficult due to fast crystallization. When the number average molecular weight is 3,000 or less, the crystallization temperature Tc of the shape memory resin can be sufficiently lowered, and the crystallization time is sufficiently long, so that the deformation operation is easily performed in a low temperature region.

  As the crystalline resin component, it is preferable to use a biodegradable one. If the crystalline resin component has biodegradability, a shape memory resin molded article having excellent biodegradability can be obtained.

(B); Linker Next, the linker used in this embodiment will be described. The linker is used to bind to the crystalline resin component and form a three-dimensional structure. As the linker, those having at least two functional groups that are bonded to the cross-linking functional group contained in the crystalline resin component are used. If the crosslinkable functional group contained in the crystalline resin component is two and the crosslinkable functional group does not form a branched structure, is the functional group contained in the linker a group capable of forming a branched structure? Alternatively, the linker needs to have three or more functional groups. However, when the number of crosslinkable functional groups contained in the crystalline resin component is 3 or more, or when the number of crosslinkable functional groups is 2 but forms a branched structure, the number of linkers is 2 or more. It suffices to have a functional group of

  As the linker, it is preferable to use a substance that forms a reversible phase in the shape memory resin molded body. Examples of such a linker include polyisocyanates having a plurality of isocyanate groups bonded to hydroxy groups. Specific examples of the polyisocyanate include carbodiimide-modified MDI, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tolylene diisocyanate, naphthylene diisocyanate, and lysine triisocyanate. Amino acid-derived lysine diisocyanate and lysine triisocyanate are substances derived from natural products, and are particularly preferably used as a linker.

  When polyisocyanate or isocyanate is used as the linker, the content thereof is preferably in the range of 0.5 to 1.5 equivalents relative to the hydrogen donor or hydrogen acceptor contained in the crystalline resin component.

(C); Additive The additive is used to lower the crystallization temperature Tc of the shape memory resin molded body. Further, it is used to slow down the crystallization speed of the shape memory resin molded body. The additive has a hydrogen acceptor or a hydrogen donor so that a hydrogen bond can be formed with the cross-linking functional group. That is, when the cross-linking functional group contained in the crystalline resin component has a hydrogen acceptor, a material having a hydrogen donor is used as an additive. When the cross-linking functional group contained in the crystalline resin component has a hydrogen donor, a material having a hydrogen acceptor is used as an additive. As the additive, a material having high compatibility with the crystalline resin component is preferably used. Further, as the additive, an additive that does not inhibit the properties of the shape memory resin by crystallization when the crystalline resin component is crosslinked with a linker is preferably used.

  The additive has two or more functional groups capable of hydrogen bonding with the cross-linked portion of the crystalline resin. The number of functional groups capable of hydrogen bonding is preferably 3 or more. If the number of functional groups is the same, the smaller the additive molecular weight, the higher the effect. That is, the equivalent amount of the hydrogen acceptor or hydrogen donor for forming a hydrogen bond is 1,000 or less, preferably 500 or less, more preferably 250 or less. As the additive, a polymer formed of the same structural unit may be used. When an additive having a high molecular weight is used, the crystallization rate can be further reduced.

  As additives, polyurethanes, polyamides, polyureas, polyhydroxys, polyethers, polyaminos and the like are preferably used.

  Examples of the polyurethane include a compound obtained by a polycondensation reaction between a polyvalent hydroxy compound and a monoisocyanate, and a compound obtained by a polycondensation reaction between a polyisocyanate and a monoalcohol.

  As the polyvalent hydroxy compound, for example, a polyhydric alcohol is used. Examples of the polyhydric alcohol include dihydric alcohols such as ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, and 1,6-hexanediol, glycerin, and trimethylolpropane. , Trivalent alcohols such as trimethylolethane, hexanetriol, castor oil, etc., tetravalent alcohols such as pentaerythritol, methylglycoside, diglycerin, polyglycerins such as triglycerin, tetraglycerin, polypenta such as dipentaerythritol, tripentaerythritol, etc. Examples include erythritol, cycloalkane polyols such as tetrakis (hydroxymethyl) cyclohexanol, and polyvinyl alcohol. Also, as its polyhydric alcohol, sugar alcohols such as adonitol, arabitol, xylitol, sorbitol, mannitol, iditol, tallitol, dulcitol, sugars such as glucose, mannose glucose, mannose, fructose, sorbose, sucrose, lactose, raffinose, cellulose, Examples thereof include coconut oil-based polyols, derivatives thereof, and modified products thereof. Moreover, a polyhydric phenol compound can also be used as a polyhydric alcohol. As the polyhydric alcohol, one type of compound may be used, or two or more types of compounds may be used.

  Examples of the monoisocyanate include at least one substance selected from the group consisting of benzyl isocyanate, acetylphenyl isocyanate, cyclohexyl isocyanate, heptyl isocyanate, hexyl isocyanate, and phenyl isocyanate.

  Examples of the polyisocyanate include at least one substance selected from the group consisting of carbodiimide-modified MDI, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tolylene diisocyanate, naphthylene diisocyanate, and lysine triisocyanate. In particular, lysine diisocyanate and lysine triisocyanate from which amino acids can be derived are preferable because they are substances derived from natural products.

  As the monohydroxy compound, for example, monoalcohol can be used. Examples of the monoalcohol include alkyl alcohols such as methanol, ethanol, and propanol. As monoalcohols, phenols can be used as well. These can be used alone or in combination of two or more.

  The content of the additive in the shape memory resin composition is preferably 50% by mass or less, more preferably 42% by mass or less, and further preferably 27% by mass or less. If the content of the additive is 42% by mass or less, the crosslinking reaction of the crystalline resin component is not hindered by the additive, and the additive is prevented from inhibiting the formation of the three-dimensional crosslinked structure. Moreover, if content of an additive is 27 mass% or less, there is no concern, such as a bleed out of an additive (C), and it is preferable. Further, the number of moles of hydrogen donor or hydrogen acceptor involved in hydrogen bonding of the additive with respect to 1 kg of the three-dimensional crosslinked body by the crystalline resin and the linker, that is, the molar concentration is 0.1 mol / kg or more. The amount is preferably, more preferably 0.2 mol / Kg or more, and still more preferably 0.4 mol / Kg or more. When the concentration of the functional group capable of hydrogen bonding is 0.1 mol / Kg or more, the crystallization temperature Tc of the shape memory resin molded product can be sufficiently lowered. The concentration of the functional group capable of hydrogen bonding is particularly preferably 0.79 mol / Kg or more.

(D); Other Additives Other additives can be added to the shape memory resin composition according to the present embodiment as long as the properties such as shape memory properties are not impaired. Examples of other additives include foaming agents, foam stabilizers, inorganic fillers, organic fillers, reinforcing materials, colorants, stabilizers (radical scavengers, antioxidants, etc.), antibacterial agents, fungicides, and flame retardants. , Plasticizers, mold release agents, impact resistance improvers, and the like. Examples of the inorganic filler include silica, alumina, talc, sand, clay, and iron slag. Examples of the organic filler include organic fibers such as polyamide fibers and plant fibers. Examples of the reinforcing material include glass fiber, carbon fiber, polyamide fiber, polyarylate fiber, acicular inorganic material, and fibrous fluororesin. Examples of antibacterial agents include silver ions, copper ions, and zeolites containing these. Examples of the flame retardant include a silicone flame retardant, a bromine flame retardant, a phosphorus flame retardant, and an inorganic flame retardant.

(Shape memory resin molding)
The shape memory resin molded body according to the present embodiment is obtained by curing the above-described shape memory resin composition. That is, a shape memory tree composition (prepolymer) is obtained by mixing and partially reacting an uncured crystalline resin component, a linker, and an additive. Then, the shape memory resin composition is adjusted to a desired shape and then cured. Thereby, the crosslinking functional group contained in the crystalline resin component is crosslinked via the linker to form a three-dimensional structure. Thereby, a shape memory resin molding is obtained. In the shape memory resin molded article, the bonding portion between the cross-linking functional group and the linker forms a stationary phase, and the crystalline resin component that connects the cross-linking functional groups forms a reversible phase.

  In the crosslinking reaction, a catalyst may be added to the shape memory resin composition as necessary. For example, when a group having a hydroxy group is used as a cross-linking functional group and a compound having an isocyanate group is used as a linker, a tertiary amine such as triethylenediamine or an organometallic compound such as dibutyltin di (2-ethylhexoate) is used as a catalyst. Etc. can be used.

  The time required for the crosslinking reaction of the crystalline resin component varies depending on the presence or absence of a catalyst and the type of functional group. For example, when both ends hydroxy polyester is used as the crystalline resin component and polyisocyanate is used as the linker, the crystalline resin component is heated to a melting temperature or higher and mixed with the polyisocyanate used as the linker, The crosslinking reaction can proceed. For example, if heated at 150 ° C., it is possible to crosslink the crystalline resin component in about 1 hour without using a catalyst, and it is possible to sufficiently crosslink in a few minutes if an appropriate catalyst is selected. It is.

  Any technique may be used as the crosslinking reaction (curing) technique. For example, a transfer molding method, a RIM molding method, a compression molding method, a foam molding method, and a photocuring molding method may be used. The obtained shape memory resin molding can be used for, for example, electrical / electronic equipment applications such as housings for electrical appliances, glasses, hearing aids, gibbs, and ballots.

  Next, the crystal melting temperature Tm and the crystallization temperature Tc of the shape memory resin molded body will be described. In this embodiment, by using an additive that forms a hydrogen bond with the cross-linking functional group of the crystalline resin component, it is possible to significantly reduce only the crystallization temperature Tc without significantly reducing the crystal melting temperature Tm. it can. Even when the crystallization temperature Tc of the crystalline resin component itself is high, the crystallization temperature Tc in the shape memory resin molded product can be lowered or the crystallization time (tc) at room temperature can be increased by the additive. .

  The shape memory resin molded body according to this embodiment can be obtained by appropriately selecting the type of resin used as the crystalline resin component, the molecular weight of the crystalline resin component, the type of linker, the type of additive, and the like. It is possible to adjust the crystallization temperature Tc.

  The melting temperature Tm of the shape memory resin molded body is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, still more preferably 100 ° C. or higher. If the melting temperature Tm is 80 ° C. or higher, sufficient heat resistance can be obtained. The melting temperature Tm is preferably 200 ° C. or lower. When the melting temperature Tm is higher than 200 ° C., thermal decomposition tends to occur when heated to a temperature equal to or higher than the melting temperature Tm. In particular, when polyesters or naturally-derived polyesters are used as the crystalline resin component, the shape memory resin molded body is likely to be thermally decomposed. The melting temperature Tm is more preferably 110 ° C. or lower. When the melting temperature Tm is 110 ° C. or lower, the shape memory resin molded body can be heated to the melting temperature Tm or higher by simple heating means such as a hair dryer, and the deformation operation can be easily performed.

  The crystallization temperature Tc of the shape memory resin molded body is preferably 45 ° C. or lower. When the crystallization temperature Tc is 45 ° C. or lower, the deformation operation and the fixing operation can be performed at room temperature (for example, 0 ° C. to 40 ° C.). When the crystallization temperature Tc exceeds 45 ° C., crystallization proceeds in the process of cooling to room temperature, so that it becomes difficult to fix the deformed shape even when deformed at room temperature, and the deformed shape can be maintained. It becomes extremely difficult. The crystallization temperature Tc is preferably −50 ° C. or higher. When the crystallization temperature Tc is −50 ° C. or higher, it is not necessary to use a special cooling means when performing immobilization.

  The temperature difference between the crystallization temperature Tc and the crystal melting temperature Tm is a scale indicating the orientation of the molecular chains in the resin, and reflects a delay in the orientation speed. If the temperature difference is 15 ° C. or more, the deformation operation can be easily performed. When the molten resin is cooled by water cooling or the like to measure the crystal state, the actual temperature of the resin is lower than the measurement temperature at the time of DSC (differential scanning calorimetry) measurement (10 ° C./min). . When the crystallization temperature Tc is 45 ° C. or lower, it takes several tens of seconds to several minutes or more at room temperature (23 ° C.) to complete crystallization. Therefore, a sufficient time margin can be provided between the cooling of the shape memory resin molded body to room temperature and the completion of crystallization. That is, the deformation operation of the shape memory resin molded body can be performed with a sufficient time margin. However, even if Tc is 45 ° C. or lower, if the crystallization time (tc) is long, Tc is not observed under normal temperature-decreasing conditions (for example, 10 ° C./min). In this case, if tc is measured by a method described later, it is possible to determine whether or not the normal temperature deformation is possible. That is, if tc is 10 seconds or more, it can be deformed at room temperature, but is preferably 20 seconds or more, and more preferably 30 seconds or more.

  By adjusting the crystallinity of the shape memory resin molding, it is possible to adjust the shape memory ability and the deformation fixing ability. The crystallinity can be adjusted by adjusting the crosslinking density of the crosslinked structure formed by the crystalline resin component. For example, the crosslinking density can be reduced by increasing the molecular weight of the precursor of the crystalline resin component. In addition, the crosslinking density can be reduced by reducing the number of crosslinking functional groups contained in the crystalline resin component. Thereby, the crystallinity degree in a shape memory resin molding can be raised. As a result, a shape memory resin molded body having a high ability to memorize the initial shape can be obtained. Conversely, the crosslink density can be increased by reducing the molecular weight of the crystalline resin component. In addition, the crosslink density can be increased by increasing the number of crosslinkable functional groups contained in the crystalline resin component. By increasing the crosslinking density, the crystallinity of the shape memory resin molded product can be reduced. By reducing the crystallinity, the elastic modulus can be reduced, and the deformation operation and the operation of fixing the deformed shape are facilitated. However, if the crosslinking density is excessively increased, the melting temperature Tm may be lowered and the heat resistance may be impaired. In addition, the stability of the deformed shape may be impaired.

  The heat of fusion of the shape memory resin molded product is preferably 20 J / g or more, more preferably 30 J / g or more. When the heat of fusion of the shape memory resin is 20 J / g or more, an intermolecular force sufficient to fix the deformed shape works, and the function as a shape memory material can be sufficiently exhibited. On the other hand, when the heat of fusion of the shape memory resin molding is less than 20 J / g, the intermolecular force may be low, and the crystallinity may be excessively reduced. As a result, the deformed shape may not be fixed.

As the shape memory resin molded body, it is preferable to use one having a storage elastic modulus (G ′ (Tm + 20)) of 2.5 × 10 ⁸ Pa or less at a temperature about 20 ° C. higher than the crystal melting temperature (Tm). The storage elastic modulus (G ′ (Tm + 20)) is more preferably 1.0 × 10 ⁸ Pa or less. Moreover, the storage elastic modulus immediately after cooling to room temperature is 1.0 × 10 ⁹ Pa or less, and the ratio between the storage elastic modulus G ′ (Tc)) after crystallization and the storage elastic modulus (G ′ (Tm + 20)). “G ′ (Tc) / G ′ (Tm + 20)” is preferably 10 or more. The ratio is more preferably 20 or more. The storage elastic modulus G ′ decreases with the activation of the micro Brownian motion accompanying the melting of the crystal phase in the temperature range equal to or higher than the crystal melting temperature (Tm). Therefore, the ratio of the storage elastic modulus G ′ at temperatures above and below the crystal melting temperature (Tm) is an index of ease of deformation. If the ratio “G ′ (Tc) / G ′ (Tm + 20)” is 10 or more, sufficient rubber properties are exhibited even in a temperature region below the crystal melting temperature Tm, and the deformation operation becomes easy.

  As the above-mentioned storage elastic modulus, a measurement value measured in a 10 Hz tensile mode using a DMS measuring device (manufactured by Seiko Instruments Inc .: DMA6100) can be employed. Specifically, the sample is heated from 20 ° C. to (Tm + 20) ° C. or higher at a rate of 2 ° C. per minute, and the storage elastic modulus during that time is measured.

  As described above, when the shape memory resin according to this embodiment is used, a shape memory resin molded body having a high melting temperature Tm and a low crystallization temperature Tc can be obtained. When the obtained shape memory resin molded body is deformed from the initial shape to a desired shape, the shape memory resin molded body has a crystal melting temperature Tm within a range not less than the crystal melting temperature and not exceeding the thermal decomposition temperature of the crystalline resin. Heat to above. Next, after quickly cooling to room temperature, a deformation operation is performed. The deformed shape is fixed by cooling below the crystallization temperature Tc. The shape memory resin molded body whose shape is fixed is maintained in its shape unless it is heated again to the melting temperature Tm or higher. Thereafter, by heating to the melting temperature Tm or higher, the initial shape is restored at a high speed and with good restoration properties. Since the deformation operation can be performed at room temperature, it can be suitably used for applications (glasses, hearing aids, casts, etc.) where it is desired to deform the shape according to the human body. Moreover, the molded object obtained by this embodiment swells with polar solvents, such as chloroform, and forms what is called a polymer gel. Since the degree of swelling increases with the amount of additive (C) added, it can be used as an oil-absorbing agent, a battery electrolyte retaining agent, and the like.

  In addition, the shape memory resin molded body according to the present embodiment is further melted by being heated to a temperature equal to or higher than the melting point of the cross-linking, that is, equal to or higher than the melting point of the shape memory resin. Thereby, re-molding is possible. Moreover, when discarding, it is decomposed | disassembled with sunlight or water by leaving it in an environment, without baking. It is also decomposed by being taken into the biocycle.

(Example)
In the following, in order to explain the present invention in more detail, examples carried out by the present inventor will be described. However, the technical scope of the present invention is not limited to the following examples.

  In the following Examples and Comparative Examples, commercially available high-purity products were used as reagents and the like unless otherwise specified. The number average molecular weight was measured by hydroxyl group concentration (A1 to 3) measured by NMR or gel permeation chromatogram method (A4) (converted using standard polystyrene).

Example 1
Dihydropolybutylene succinate (A1) was prepared as a crystalline resin component. 118 g (1.00 mol) of succinic acid and 95 g (1.05 mol) of 1,4-butanediol were charged into a 1 L separable flask equipped with a stirrer, a shunt condenser, a thermometer, and a nitrogen introducing tube. And dehydration condensation was performed for 7 hours at 180-220 degreeC in nitrogen atmosphere. The obtained product was dissolved in chloroform and washed with alkali. Then, it was reprecipitated with methanol. As a result, a polybutylene succinate (A1) having a number average molecular weight (NMR) of 2000 and having hydroxyl groups at both ends was obtained.

Tris (6-ethoxycarbonylaminohexyl) isocyanurate was prepared as an additive. Commercially available polyisocyanate (Asahi Kasei Chemicals, TPA-100) (B1) 100 g and ethanol 40 g were refluxed in chloroform for 2 hours. Thereafter, excess ethanol and chloroform were distilled off to obtain additive (C1).

Polyisocyanate (B1) was prepared as a linker .

Next, 10.0 g of dihydropolybutylene succinate (A1), 1.0 g of additive (C1), and 1.8 g of polyisocyanate (B1) were melt-mixed at 180 ° C. to obtain a shape memory resin composition. The shape memory resin composition was poured into a mold and held at 180 ° C. for 1 hour. As a result, the crosslinking reaction proceeded, and the shape memory resin molded body according to Example 1 was obtained.

  About the obtained shape memory resin molding, the crystallization temperature (Tc), crystal heating (Hc), crystal melting temperature (Tm), crystallization heat (Hm), and crystallization time (tc) were determined by the following methods. It was measured. Moreover, shape memory property and normal temperature deformability were evaluated. The results are shown in Table 1.

[Crystallization temperature (Tc), crystal melting temperature (Tm), heat of fusion (Hm), crystallization time (tc)]
Using a DSC measuring apparatus (trade name: DSC6000) manufactured by Seiko Instruments Inc., measurement is performed at a temperature drop rate of 10 ° C./min from the melting temperature (high temperature region), and the crystallization temperature (Tc) of the shape memory resin molded body is determined. Asked. Subsequently, measurement was performed at a rate of temperature increase of 10 ° C./min (from a low temperature range), and the crystal melting temperature (Tm) and the heat of fusion (Hm) were measured. Furthermore, it cooled from the melting temperature (high temperature region) to 20 ° C. at a temperature decrease rate of 20 ° C./min, and the time until the crystallization peak was observed (crystallization time: tc) was measured. When the crystallization temperature Tc exceeds 45 ° C., crystallization occurs before being cooled to 20 ° C., so that the crystallization time tc is not observed. When the crystallization time tc was not observed, it was evaluated as “x”.

[Normal temperature deformability]
A shape memory resin molded body having a shape (first shape) of 2 cm × 5 cm × 1.0 mm was prepared. This shape memory resinous shape was heated at a temperature of the melting temperature Tm + 20 ° C., and the center portion was bent at 30 ° to be deformed. After the deformation, it was cooled in a 23 ° C. water bath and retained its shape for 30 minutes. Thereby, the shape memory resin molding of the 2nd shape was obtained. The angle (Y ₁ ) of the bent portion of the obtained shape memory resin molding was determined, and the room temperature deformability of the shape memory was evaluated according to the following criteria.

When 20 ° ≦ Y ₁ ≦ 30 °, it was evaluated as “good”.
The case of 10 ° ≦ Y ₁ <20 ° was evaluated as Δ.
The case of 0 ° ≦ Y ₁ <10 ° was evaluated as x.

[Restorability]
The shape memory resin molded body of the second shape was heated at “melting temperature Tm + 20 ° C.” with a hot water bath. The angle (Y ₂ ) of the bent portion of the shape memory resin molded body after heating was measured, and the restorability was evaluated using the following criteria.

When 20 ° ≦ Y ₂ ≦ 30 °, it was evaluated as x.
It was evaluated as Δ when 10 ° ≦ Y ₂ <20 °.
When 0 ° ≦ Y ₂ <10 °, it was evaluated as “good”.

(Example 2)
As an additive (C1), 2.0 g was used. The other conditions were the same as in Example 1, and a shape memory resin molded body according to Example 2 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Example 3)
4.0 g was used as additive (C1). The other conditions were the same as in Example 1, and a shape memory resin molded body according to Example 3 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

Example 4
Dihydropolybutylene succinate (A2) was prepared as a crystalline resin component. A 1 L separable flask equipped with a stirrer, a shunt condenser, a thermometer, and a nitrogen introduction tube was charged with 118 g (1.0 mol) of succinic acid and 95 g (1.05 mol) of 1,4-butanediol under a nitrogen atmosphere. Dehydration condensation was performed at 180 to 220 ° C. for 7 hours. Subsequently, the dediol reaction was performed under reduced pressure at 180 to 220 ° C. for 1.0 hour. Then, it was reprecipitated with chloroform and methanol. As a result, a polybutylene succinate (A2) having a number average molecular weight (NMR) of 3000 and having hydroxyl groups at both ends was obtained.

Shape memory as in Example 1, using 10.0 g of dihydropolybutylene succinate (A2), 1.0 g of additive (C1) obtained in Example 1, and 1.2 g of polyisocyanate (B1) A resin molded body was obtained. About the obtained molded object, Tc, Tm, and Hm were measured like Example 1, and shape memory property and normal temperature deformation were evaluated.

(Example 5)
2.0 g of additive (C1) was used. The other conditions were the same as in Example 4, and the shape memory resin molded body according to Example 5 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Example 6)
4.0 g of additive (C1) was used. The other conditions were the same as those in Example 4, and the shape memory resin molded body according to Example 6 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Example 7)
8.0 g of additive (C1) was used. The other conditions were the same as in Example 4, and the shape memory resin molded body according to Example 7 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Example 8)
Dihydropolybutylene succinate (A4) was prepared as a crystalline resin component. In a 1 L separable flask equipped with a stirrer, a shunt condenser, a thermometer, and a nitrogen introduction tube, succinic acid 118 g (1.0 mol), 1,4-butanediol 108 g (1.2 mol), and tetraisopropyl titanate 0.02 g was charged. Dehydration condensation was performed at 180 to 220 ° C. for 4 hours in a nitrogen atmosphere. Subsequently, a dediol reaction was performed at 180 to 220 ° C. under reduced pressure for 13 hours. As a result, a polybutylene succinate (A4) having a number average molecular weight (NMR) of 10,500 and having hydroxyl groups at both ends was obtained.

The same conditions as in Example 1 were obtained using 10.0 g of the obtained dihydropolybutylene succinate (A4), 8.0 g of the additive (C1) prepared in Example 1, and 0.35 g of polyisocyanate (B1). Thus, a shape memory resin molded body according to Example 8 was obtained. About the obtained shape memory resin molding, Tc, Hm, Tm, Hm, and tc were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Comparative Example 1)
The additive (C1) was not used. The other conditions were the same as in Example 1, and a shape memory resin molded body according to Comparative Example 1 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Comparative Example 2)
The additive (C1) was not used. The other conditions were the same as those in Example 4, and a shape memory resin molded body according to Comparative Example 2 was obtained. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

(Comparative Example 3)
Dihydropolybutylene succinate (A3) was prepared as a crystalline resin component. 118 g (1.0 mol) of succinic acid and 95 g (1.05 mol) of 1,4-butanediol were charged into a 1 L separable flask equipped with a stirrer, a shunt condenser, a thermometer, and a nitrogen introduction tube. And dehydration condensation was performed for 2 hours at 180-220 degreeC in nitrogen atmosphere. The obtained product was dissolved in chloroform and washed with alkali. Then, it reprecipitated with methanol. As a result, a polybutylene succinate (A3) having a number average molecular weight (NMR) of 1000 and having hydroxyl groups at both ends was obtained.

Using the obtained dihydropolybutylene succinate (A3) 10.0 g and polyisocyanate (B1) 3.64 g, a shape memory resin molded article according to Comparative Example 3 was obtained. In the same manner as in Example 1, Tc, Tm, and Hm were measured, and shape memory properties and room temperature deformation were evaluated.

(Comparative Example 4)
Except that the additive was not added, the same conditions as in Example 8 were adopted to obtain a shape memory resin molded body according to Comparative Example 4. About the obtained molded object, Tc, Tm, and Hm were measured similarly to Example 1, and shape memory property and normal temperature deformation were evaluated.

In Table 1, in Examples 2, 3, 6, 7, and Comparative Example 3, the crystallization temperature Tc is not observed, it was not possible to determine the heat of crystallization _{H D.} As described above, when the crystallization speed is low, the crystallization temperature Tc is not observed. That is, in Examples 2, 3, 6, 7 and Comparative Example 3, it is shown that the crystallization rate is sufficiently low. In Comparative Examples 2 and 4, the crystallization time Tc could not be obtained. This is because crystallization occurred before reaching room temperature.

  In Table 1, Examples 1 to 3 are compared with Comparative Example 1. Examples 1 to 3 and Comparative Example 1 were all excellent in shape memory properties (normal temperature deformability and recoverability). However, the crystal melting temperature Tm of Examples 1 to 3 is higher than the crystal melting temperature Tm of Comparative Example 1. That is, it was confirmed that Examples 1 to 3 were superior to Comparative Example 1 in heat resistance. Further, Example 1 had a crystallization temperature Tc lower than that of Comparative Example 1. In Examples 2 and 3, the crystallization temperature Tc was not observed. Therefore, Examples 2 and 3 could not compare the crystallization temperature Tc with Comparative Example 1. However, Examples 1 to 3 had a longer crystallization time Tc than Comparative Example 1. That is, in Examples 1 to 3, it is shown that the time during which the deformation operation can be performed after cooling to room temperature is long. That is, it was confirmed that Examples 1 to 3 were easier to perform the deformation operation when cooled to room temperature than Comparative Example 1. That is, it was confirmed that by using the additive (C1), a shape memory resin molded body having high heat resistance and easy to perform a deformation operation can be obtained.

  In Table 1, Examples 4 to 7 are compared with Comparative Example 2. In Examples 4 to 7 and Comparative Example 2, a resin having a molecular weight of 3,000 is used as the crystalline resin component. Among these, in Examples 4 to 5, the crystallization temperature Tc was 45 ° C., and the shape memory property (normal temperature deformability and recoverability) was excellent. In Examples 6 and 7, the crystallization rate was slow and Tc was not observed, but tc was 0.5 minutes or more, and deformation at room temperature was easy. However, in Comparative Example 2, the crystallization temperature Tc was 53 ° C. and significantly exceeded 45 ° C. In Comparative Example 2, when rapidly cooled, crystallization occurred before reaching normal temperature, and could not be deformed (shaped) at normal temperature. From these results, it was confirmed that Examples 4 to 5 were superior to Comparative Example 2 in normal temperature deformability. Further, the melting temperatures of Examples 4 to 5 were all 80 ° C. or higher, and did not decrease much compared to Comparative Example 2. That is, it was confirmed that by adding the additive (C1), the normal temperature deformability can be enhanced while maintaining the heat resistance.

  Example 8 is compared with Comparative Example 4. In Example 8, the crystallization temperature Tc was lower than that of Comparative Example 4. Further, the room temperature deformability of Example 8 was superior to that of Comparative Example 4. On the other hand, the melting temperature Tm of Example 8 was higher than that of Comparative Example 4, and it was confirmed that the heat resistance was superior to that of Comparative Example 4. That is, it was confirmed that both the room temperature deformability and the heat resistance can be achieved by adding the additive (C1).

  In addition, from the measurement results of Examples 1 to 8, Examples 1 to 7 having a molecular weight of 2,000 to 3,000 have better room temperature deformability than Example 8 having a molecular weight of 10,500. It was. From this, it was confirmed that the molecular weight of the crystalline resin component is preferably 2,000 or more and 3,000 or less.

  The shape memory resin molded body according to this embodiment can be deformed at room temperature and has excellent shape memory properties. Therefore, it can be suitably used as a molded article such as a member for electronic equipment. For example, exterior materials for electronic devices (such as personal computers and mobile phones), screws, clamping pins, switches, sensors, information recording devices, rollers for OA equipment, parts such as belts, packing materials for sockets, pallets, etc., air conditioning air conditioners It can be used for open / close valves and heat-shrinkable tubes. In addition, the shape memory resin molded body according to the present embodiment can be used in various fields as automobile members such as bumpers, handles, and rearview mirrors, and household members such as bed slip prevention bedding. In addition, it can be deformed and fixed at room temperature, and has heat resistance, so that it can be handled without worrying about burns. Therefore, it can be used for applications (for example, casts, toys, eyeglass frames, orthodontic wires, hearing aids, casts, etc.) that are deformed and fixed according to the body shape.

Claims (15)

A crystalline resin component having a plurality of cross-linking functional groups;
A linker that crosslinks the crystalline resin component by binding to a plurality of the crosslinking reactive groups ;
Containing additives,
The crosslinking site formed by the bond between the crystalline resin component and the linker and the additive can form a hydrogen bond,
The crystalline resin component comprises polyhydroxypolyester,
The linker has two or more functional groups that bind to the cross-linking functional group contained in the crystalline resin component;
The shape memory resin composition, wherein the additive comprises a polyurethane .   The cross-linked site formed by the bond between the crystalline resin component and the linker has a hydrogen donor or hydrogen acceptor in a hydrogen bond, and the additive has a hydrogen acceptor or hydrogen donor in a hydrogen bond. The shape memory resin composition described in 1. The shape memory resin composition according to claim 1 or 2 , wherein the polyhydroxypolyester contains polyhydroxypolybutylene succinate. The shape memory resin composition according to claim 1 , wherein the linker contains polyisocyanate. The shape memory resin composition according to any one of claims 1 to 4 , wherein the additive contains a compound obtained by a polymerization reaction of a polyvalent hydroxy compound and monoisocyanate . The shape memory resin composition according to any one of claims 1 to 4 , wherein the additive contains a compound obtained by a polymerization reaction of polyisocyanate and monoalcohol . The shape memory resin composition according to claim 1 , wherein the additive contains tris (6-ethoxycarbonylaminohexyl) isocyanurate . The hydrogen donor or hydrogen acceptor contained in the additive has a molar concentration of 0.4 mol / kg or more, and the content of the additive is 42% by mass or less in the shape memory resin composition. The shape memory resin composition according to any one of claims 1 to 7 . The shape memory resin composition according to any one of claims 1 to 8 , wherein the crystalline resin component has an average molecular weight of 2,000 or more and 3,000 or less. The crystalline resin component shape-memory resin composition according to any one of claims 1 to 9 have biodegradability. Crystalline melting temperature (Tm) is not less 80 ° C. or higher, the crystallization temperature (Tc) is 45 ° C. or less, or crystallization time (tc) is greater than or equal to 0.5 minutes, any one of claims 1 to 10 The shape memory resin composition described in 1. A shape memory resin molded article obtained by curing the shape memory resin composition according to any one of claims 1 to 11 .   The shape memory resin molded article according to claim 12, wherein the heat of fusion is 20 J / g or more.   The storage elastic modulus (G ′ (Tm + 20)) at 20 ° C. higher than the crystal melting temperature (Tm) is 2.5 × 10 ⁸ The storage elastic modulus (G ′ (Tc)) after crystallization has a relationship of (G ′ (Tc)) / (G ′ (Tm + 20)) ≧ 10. The shape memory resin molded product according to any one of the above. A step of preparing the shape memory resin composition according to any one of claims 1 to 13 , a step of making the shape of the shape memory resin composition a desired shape, and a step of making the desired shape And a step of crosslinking the crystalline resin component via the linker to obtain a molded product.

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