JP2006342196A - Resin composition and molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a resin composition for improving a crystallization rate and crystallinity and molding. <P>SOLUTION: The resin composition comprises a mixture as a main component obtained by mixing a polybutylene succinate with a phenoxy resin. The mixing ratio of the phenoxy resin in the mixture is ≤35 mass%. The molding is obtained by using the resin composition. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a resin composition and a molded article having an improved crystallization rate of polybutylene succinate.

  In recent years, due to increasing environmental problems, when plastic products are discarded in the natural environment, it is beginning to be required to decompose and disappear over time and ultimately not have a negative impact on the natural environment. Conventional plastics are stable in the natural environment for a long period of time and have a low bulk specific gravity. Therefore, it has been pointed out that problems such as promoting the shortening of the life of landfills and damaging the natural landscape and the living environment of wild animals and plants It had been.

  Therefore, biodegradable resin materials are attracting attention today. Biodegradable resins are known to gradually disintegrate and decompose by hydrolysis and biodegradation in soil and water, and finally become harmless degradation products due to the action of microorganisms. It is also known that waste can be easily treated by composting (composting).

  Biodegradable resins that have begun to be put into practical use include aliphatic polyesters, modified PVA, cellulose ester compounds, starch modified products, and blends thereof.

  Each of these biodegradable plastics has unique characteristics and can be used in accordance with these characteristics. Among them, aliphatic polyesters having a wide range of properties and processability similar to general-purpose resins are beginning to be widely used. Among aliphatic polyesters, polybutylene succinate is an alternative material for polypropylene and polystyrene in the field of film, sheet, and injection molding because of its high crystallization speed, high crystallinity, and excellent heat resistance. It has potential.

  However, although polybutylene succinate has a high crystallization rate, crystallization may not be completed by a normal molding method, and there is a concern about shrinkage after molding and dimensional change due to shrinkage during use. Further improvement in crystallization speed and improvement in crystallinity may be required.

  Japanese Patent Application Laid-Open No. 9-169893 discloses a method of blending a layered silicate in order to improve the crystallization rate of polybutylene succinate. Since the performance has not improved, there has been a problem in practical use.

Japanese Patent Laid-Open No. 9-169893

  The present invention has been made to solve the above problems, and an object of the present invention is to further improve the crystallization rate of polybutylene succinate and improve the crystallinity. It is to provide a product and a molded body.

  The resin composition of the present invention is a resin composition containing, as a main component, a mixture of polybutylene succinate and phenoxy resin, and the mixing ratio of the phenoxy resin is 35% by mass or less in the mixture. Features.

  The molded product of the present invention is characterized by using any of the above resin compositions. Moreover, the said molded object can be a film, a sheet | seat, or an injection molded object.

  According to the present invention, by blending a phenoxy resin, it is possible to further improve the excellent crystallization rate inherent in polybutylene succinate, and to provide a resin composition and a molded body that can improve crystallinity. be able to.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described below.
The resin composition of the present invention contains a mixture of polybutylene succinate and phenoxy resin as a main component.

  The polybutylene succinate used in the present invention is obtained by polymerizing succinic acid and 1,4-butanediol. As polybutylene succinate, for example, “GSPla” series manufactured by Mitsubishi Chemical Corporation, “Bionore” series manufactured by Showa High Polymer Co., Ltd., and the like are commercially available.

  Examples of the phenoxy resin used in the present invention include hydroquinone, resorcin, 4,4′-bisphenol, 4,4′-dihydroxydiphenyl ether, bisphenol A, bisphenol F, and aromatic dihydroxy compounds such as 2,6-dihydroxynaphthalene, Alternatively, one kind selected from aliphatic dihydroxy compounds such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol, neopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, or And polyhydroxy polyethers obtained by condensing two or more compounds with glycerin and epichlorohydrin. It is. Representative examples of commercially available phenoxy resins include Epicoat (registered trademark) E1256, E4250, E4275 manufactured by Japan Epoxy Resin Co., Ltd., PKHH, PKHC, PKHJ, PKHB, PKFE manufactured by InChem.

  As the blending amount of the phenoxy resin, the proportion of the phenoxy resin in the mixture of polybutylene succinate and phenoxy resin is 35% by mass or less, preferably 0.1% by mass or more and 30% by mass or less, More preferably, it is 3 mass% or more and 15 mass% or less. When the blending ratio of the phenoxy resin exceeds 35% by mass, the crystallization of polybutylene succinate is inhibited by the phenoxy resin, so that the crystallization speed and the crystallinity are remarkably reduced.

  By the way, for example, in the case of polybutylene terephthalate (PBT) even in the case of aliphatic polyester, there is a phenomenon that when phenoxy resin is blended with polybutylene terephthalate, the glass transition temperature (Tg) of polybutylene terephthalate is lowered and the crystallinity is lowered. occured. However, it has been found that when a phenoxy resin is added to polybutylene succinate as in the present invention, the reverse phenomenon occurs in which the glass transition temperature (Tg) of polybutylene succinate increases. Moreover, even if a phenoxy resin was blended with polyethylene terephthalate (PET), no increase in the glass transition temperature (Tg) was observed. Therefore, polybutylene succinate was able to achieve surprisingly that the improvement in crystallinity could not be achieved with other aliphatic polyesters or the like even if a phenoxy resin was added.

  To the resin composition of the present invention, additives such as a heat stabilizer, an antioxidant, a UV absorber, a light stabilizer, a pigment, a colorant, a lubricant, a plasticizer and the like are added within a range not impairing the effects of the present invention. Can be blended.

Next, a method for forming a molded body using the resin composition of the present invention will be described.
Each raw material such as polybutylene succinate, phenoxy resin, and additives as necessary can be put into the same extruder or injection molding machine, kneaded directly, and molded to form a molded body. . Alternatively, a dry blended raw material is extruded into a strand shape using a twin-screw extruder to produce pellets, and the pellets are placed in an injection molding machine, an extruder, etc., and molded to form a film, sheet, injection molding A molded body such as a body can be formed.

  Whichever method is employed, it is necessary to consider the molecular weight reduction of polybutylene succinate, but the latter is preferably selected in order to uniformly mix the raw materials. For example, polybutylene succinate, phenoxy resin, and additives as necessary are thoroughly dried to remove moisture, then melt mixed using a twin screw extruder, extruded into a strand shape, and pellets Make it. In addition, it is preferable to select the melt extrusion temperature appropriately in consideration of the viscosity of the mixture (mixed resin) changing depending on the mixing ratio with polybutylene succinate, phenoxy resin, and additives. In practice, a temperature range of 160 ° C. to 230 ° C. is usually selected.

  After pellets produced by the above method are sufficiently dried to remove moisture, a molded body such as a film, a sheet, or an injection molded body is formed. A roll stretching method, a tenter stretching method, a tubular method, an inflation method, or the like is employed as a molding method for a film, a sheet, and the like. Is adopted.

  As a method for producing an injection-molded body, for example, an injection molding method such as an injection molding method, a gas assist molding method, or an injection compression molding method generally employed when molding a thermoplastic resin can be employed. In addition to the above methods, an in-mold molding method, a gas press molding method, a two-color molding method, a sandwich molding method, PUSH-PULL, SCORIM, or the like can also be employed in accordance with other purposes. However, the injection molding method is not limited to these.

  The injection molding apparatus used is a general injection molding machine, gas assist molding machine, injection compression molding machine, etc., molding molds and incidental equipment used in these molding machines, mold temperature control device, raw material drying device Etc. The molding conditions are preferably such that the molten resin temperature is in the range of 160 ° C to 230 ° C in order to avoid thermal decomposition of the resin in the injection cylinder.

According to the present invention, the crystal speed of polybutylene succinate can be further improved, so that a molded body with sufficient crystallization can be realized even if the molded body is formed by a normal molding method. . Therefore, there is no need to worry about dimensional changes due to shrinkage after molding and shrinkage at the time of use, and a molded article having excellent dimensional stability can be obtained.

  The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples, and various applications are possible without departing from the technical scope of the present invention. In addition, the sheet | seat obtained in each Example and each comparative example measured by the method shown below, and obtained crystallization temperature (Tc) and the amount of heat of crystal fusion ((DELTA) Hm).

Measurement of crystallization temperature (Tc) and heat of crystal melting (ΔHm):
Based on Japanese Industrial Standards JIS K7121, about 10 mg cut out as a measurement sample was measured according to the following procedure using a differential scanning calorimeter “DSC-7” manufactured by PerkinElmer.
(1) First, the temperature was raised from 30 ° C. to 200 ° C. at a rate of 500 ° C./min, and then held at 200 ° C. for 2 minutes.
(2) Next, the temperature was lowered from 200 ° C. to 30 ° C. at a rate of 10 ° C./min to prepare a thermogram.
(3) Then, it heated up from 30 degreeC to 200 degreeC with the speed | rate of 10 degree-C / min, and produced the thermogram.

The crystallization temperature (Tc) was read from the thermogram obtained in the temperature lowering process (2). Further, the heat of crystal melting (ΔHm) was read from the thermogram obtained in the re-heating process of (3) above.
The crystallization temperature (Tc) is an index of the crystallization rate, and the higher the Tc, the faster the crystallization rate. Further, the heat of crystal fusion (ΔHm) is an index of crystallinity, and the higher the heat of crystal fusion (ΔHm), the higher the crystallinity. In the present invention, the crystallization temperature (Tc) and the heat of crystal fusion (ΔHm) of polybutylene succinate are determined from the crystallization temperature (Tc) and the heat of crystal fusion (ΔHm) of the mixture containing phenoxy resin in polybutylene succinate. Low is important. In particular, the crystallization temperature (Tc) is preferably 75 ° C. or higher, and the heat of crystal fusion (ΔHm) is preferably 55 J / g or higher.

Example 1
GSPla AZ91T (weight average molecular weight 160,000) manufactured by Mitsubishi Chemical Corporation was used as the polybutylene succinate, and Epicoat (registered trademark) E1256 (bisphenol A type) manufactured by Japan Epoxy Resin Co., Ltd. was used as the phenoxy resin. GSPla AZ91T and E1256 were mixed in a mass ratio of 99 parts by mass: 1 part by mass, kneaded at 200 ° C. using a 40 mmφ single screw extruder manufactured by Mitsubishi Heavy Industries, Ltd., and then extruded from the die. Subsequently, the sheet was quenched by being brought into contact with a casting roll at 45 ° C. to prepare a sheet having a thickness of 200 μm.

  About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 2)
A sheet was produced in the same manner as in Example 1 except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed so that GSPla AZ91T: E1256 = 95: 5 by mass ratio.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 3)
A sheet was prepared in the same manner as in Example 1, except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed to GSPla AZ91T: E1256 = 90: 10 by mass ratio. It was.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

Example 4
A sheet was prepared in the same manner as in Example 1 except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed to GSPla AZ91T: E1256 = 85: 15 by mass ratio. It was.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 5)
A sheet was prepared in the same manner as in Example 1, except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed to GSPla AZ91T: E1256 = 80: 20 by mass ratio. It was.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 6)
In Example 1, E4250 (bisphenol A / bisphenol F = 50/50 type) manufactured by Japan Epoxy Resin Co., Ltd. was used instead of E1256 as the phenoxy resin, and the blending ratio of polybutylene succinate and phenoxy resin was determined by mass ratio. Thus, a sheet was produced in the same manner as in Example 1 except that GSPla AZ91T: E4250 = 90: 10.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 7)
In Example 1, E4275 (bisphenol A / bisphenol F = 25/75 type) manufactured by Japan Epoxy Resin Co., Ltd. was used as the phenoxy resin instead of E1256, and the blending ratio of polybutylene succinate and phenoxy resin was determined by mass ratio. Thus, a sheet was prepared in the same manner as in Example 1 except that GSPla AZ91T: E4250 = 90: 10.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Example 8)
A sheet was produced in the same manner as in Example 1 except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed so that the mass ratio was GSPla AZ91T: E1256 = 70: 30.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

Example 9
A sheet was produced in the same manner as in Example 1 except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed to GSPla AZ91T: E1256 = 97: 3 in terms of mass ratio.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 1.

(Comparative Example 1)
A sheet made of polybutylene succinate GSPla AZ91T was produced without using a phenoxy resin. That is, polybutylene succinate GSPla AZ91T was kneaded at 200 ° C. using a 40 mmφ single screw extruder manufactured by Mitsubishi Heavy Industries, Ltd., then extruded from the die, and then rapidly cooled by contacting with a 45 ° C. casting roll. A 200 μm thick sheet was produced.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

(Comparative Example 2)
A sheet was produced in the same manner as in Example 1, except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed to GSPla AZ91T: E1256 = 60: 40 by mass ratio.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

(Comparative Example 3)
A sheet was produced in the same manner as in Example 1 except that the blending ratio of polybutylene succinate and phenoxy resin in Example 1 was changed so that the mass ratio was GSPla AZ91T: E1256 = 40: 60.
The obtained sheet was subjected to the measurement for evaluating the crystallization speed and the degree of crystallization in the same manner as in Example 1. As a result, both the crystallization temperature (Tc) and the crystallization heat quantity (ΔHm) Did not appear.

(Comparative Example 4)
In Example 1, instead of phenoxy resin, using Microace L1 (talc, average particle size 4.9 μm) manufactured by Nippon Talc Co., Ltd., the blending ratio of polybutylene succinate and talc in mass ratio, GSPla AZ91T: A sheet was prepared in the same manner as in Example 1 except that the microace L1 was changed to 90:10.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

(Comparative Example 5)
A 200 μm thick sheet made of polyethylene terephthalate (Unipet RT523C, IV = 0.2 manufactured by Nippon Unipet Co., Ltd.) was produced. That is, polyethylene terephthalate (Unipet RT523C) was kneaded at 200 ° C. using a 40 mmφ single screw extruder manufactured by Mitsubishi Heavy Industries, Ltd., extruded from a die, and then rapidly cooled by contacting with a 45 ° C. casting roll. A sheet having a thickness of 200 μm was prepared.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

(Comparative Example 6)
In Comparative Example 5, a phenoxy resin (E1256) was further added to polyethylene terephthalate (Unipet RT523C), and the mixture was blended so that Unipet RT523C: E1256 = 80: 20 by mass ratio. A 200 μm thick sheet was produced.
About the obtained sheet | seat, the measurement similar to Example 1 etc. were performed. The results are shown in Table 2.

(Comparative Example 7)
A sheet composed of polylactic acid (Nature Works 4032D manufactured by Nature Works LLC) (L-lactic acid / D-lactic acid = 98.5 / 1.5, weight average molecular weight 200,000) was prepared, that is, polylactic acid (Nature Works 4032D). ) Was kneaded at 200 ° C. using a 40 mmφ single screw extruder manufactured by Mitsubishi Heavy Industries, Ltd., then extruded from the die, and then rapidly cooled by contacting with a 45 ° C. casting roll to produce a 200 μm thick sheet. .
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

(Comparative Example 8)
A sheet having a thickness of 200 μm was prepared in the same manner as in Comparative Example 7, except that a phenoxy resin (E1256) was further used in Comparative Example 7 and blended so that the mass ratio was Nature Works 4032D: E1256 = 80: 20.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2. The crystallization temperature (Tc) did not appear on the thermogram.

(Comparative Example 9)
In Example 1, instead of phenoxy resin, layered silicate (fluorine mica-based mineral, ME100 manufactured by Co-op Chemical Co., Ltd.) was used, and the blending ratio of polybutylene succinate and layered silicate in terms of mass ratio was GSPla AZ91T. : A sheet was produced in the same manner as in Example 1 except that ME100 was changed to 95: 5.
About the obtained sheet | seat, the crystallization temperature (Tc) and the crystal heat of fusion ((DELTA) Hm) were calculated | required. The results are shown in Table 2.

  Since Comparative Example 1 in Table 2 is a sheet made of polybutylene succinate, Tc is 72 ° C. and ΔHm is 54 J / g, the effect of the present invention will be considered while comparing with these values. As is apparent from Table 1, Tc of the injection-molded bodies (sheets) made of the resin compositions of Examples 1 to 9 is improved from Tc = 72 ° C. in Comparative Example 1, and Tc is 75 ° C. In addition, the heat of crystallization (ΔHm) of the sheets made of the resin compositions of Examples 1 to 9 is improved from ΔHm = 54 J / g of Comparative Example 1, and ΔHm is 55 J / g. It turns out that it is above. That is, by blending a polybutylene succinate with a phenoxy resin, it is possible to obtain a result with a more preferable level of Tc of 75 ° C. or more and ΔHm of 55 J / or more, an improvement in crystallization speed, and sufficient crystallization. It turned out to be complete.

  On the other hand, as is clear from Table 2, since the sheet composed of the resin composition of Comparative Examples 2 to 3 has too much blending ratio of the phenoxy resin blended with polybutylene succinate, both Tc and ΔHm are those of Comparative Example 1. Tc = 72 ° C. and ΔHm = 54 J / g, indicating that both the crystallization speed and the degree of crystallization were inferior. In addition, the sheet made of the resin composition of Comparative Example 4 in which talc was blended instead of phenoxy resin was not sufficiently improved although Tc was improved by 1 ° C., ΔHm was not improved, and crystallization was sufficient. Was not completed. The sheet made of the resin composition of Comparative Examples 5 and 6 is a sheet using polyethylene terephthalate instead of polybutylene succinate, and the sheet of Comparative Example 6 in which phenoxy resin is blended with PET does not blend with phenoxy resin. When compared with the sheet of Comparative Example 5, it was found that the crystallization temperature (Tc) was not improved and ΔHm was lowered. Comparative Examples 7 and 8 are sheets using polylactic acid instead of polybutylene succinate, and the sheet of Comparative Example 8 in which phenoxy resin is blended with polylactic acid is the sheet of Comparative Example 7 in which phenoxy resin is not blended. , The crystallization temperature (Tc) did not appear in the thermogram, and no improvement in ΔHm was observed. The sheet of Comparative Example 9 is a sheet in which layered silicate is blended with polybutylene succinate, and the crystallization temperature (Tc) is increased as compared with the sheet of Comparative Example 1 in which layered silicate is not blended. However, the heat of crystal fusion (ΔHm) decreases. That is, it can be seen that the crystallization speed increased but the crystallinity decreased.

  That is, as is clear from the above Examples and Comparative Examples, polybutylene succinate can be blended with talc known as a nucleating agent other than phenoxy resin, such as polylactic acid and PET, or polylactic acid and PET. Even if a phenoxy resin is blended with the phenoxy resin, both the improvement of Tc and the improvement of ΔHm are not recognized at the same time, and the excellent effect of the present invention is achieved only by blending the phenoxy resin with polybutylene succinate. I understood.

  As described above, according to the present invention, it is possible to obtain a resin composition and a molded body that can further improve the crystallization rate of polybutylene succinate and can sufficiently complete crystallization. . Therefore, it is possible to realize a molded body that does not shrink after molding or does not undergo dimensional changes due to shrinkage during use.

  The resin composition of the present invention has characteristics such as biodegradability, high crystallinity, and heat resistance of polybutylene succinate, and can sufficiently complete crystallization, so these characteristics are required. For example, it can be used for home appliances and automobile products. In addition, it can also be used as electrical and electronic equipment parts, daily necessities, food containers, and other general injection molded products.

Claims (3)

  A resin composition comprising, as a main component, a mixture of polybutylene succinate and a phenoxy resin, wherein the blending ratio of the phenoxy resin is 35% by mass or less in the mixture.   A molded body comprising the resin composition according to claim 1. The molded body according to claim 2, wherein the molded body is a film, a sheet, or an injection molded body.