Resin composition for foam defibration molding, foam defibration molding, method for molding foam defibration molding, and foam defibration sheet

Abstract

To provide a resin composition capable of manufacturing a foam defibration molding in which fibers are packed more denser, and foams are formed more uniform.SOLUTION: A resin composition for foam defibration molding contains a polycarboxylic acid ester (A) and a polycarboxylic acid ester (B). The melt flow rate (MFR(A)) of the polycarboxylic acid ester (A) at 210°C and a load of 2.16 kg, measured according to ASTM D1238, is 0.1 g / 10 minutes or more and 100 g / 10 minutes or less. The melt flow rate (MFR(B)) of the polycarboxylic acid ester (B) at 210°C and a load of 2.16 kg, measured according to ASTM D1238, is 0.1 g / 10 minutes or more and 100 g / 10 minutes or less. The MFR(A) is greater than the MFR(B), and the MFR(A) and MFR(B) satisfy the MFR ratio represented by the following formula (I). (I) Formula 1.3≤MFR(A) / MFR(B)≤100.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition for foam defibration molding, a foam defibrated molded body, a method for molding a foam defibrated molded body, and a foam defibrated body sheet. [Background technology]

[0002] Molded bodies (foamed defibrated moldings) are known that are produced by melt-extruding a resin while foaming it, and then stretching and defibrating the foamed extrudate. Known resins used to produce foamed defibrated moldings include polyethylene terephthalate, aliphatic polyesters obtained by reacting glycols with aliphatic dibasic acids (succinic acid, adipic acid, etc.) (Patent Documents 1 and 2, etc.), and polylactic acid (Patent Document 3, etc.). These documents state that foamed defibrated moldings can be used for a variety of purposes, such as adsorbents for oil and suspended solids, nonwoven fabrics, filtration materials, adhesive materials, and packaging materials. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-172578 [Patent Document 2] Japanese Patent Application Publication No. 8-325918 [Patent Document 3] Japanese Patent Application Publication No. 5-177734 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when using a foamed defibrated molding as an adsorbent or filter, it is believed that adsorption efficiency will be improved if the fibers of the foamed defibrated molding are made denser, the surface area is increased, and the cells are made more uniform. Also, when used as a nonwoven fabric, it is believed that the appearance can be improved by making the fibers denser and the cells more uniform. Furthermore, by making the fibers denser and the cells more uniform, it is possible to make the foamed defibrated molding lighter while still achieving the above effects.

[0005] In view of these circumstances, an object of the present invention is to provide a resin composition that can produce a foamed, defibrated molding with denser fibers and more uniform bubbles, a foamed, defibrated molding produced from the resin composition, a method for molding a foamed, defibrated molding using the resin composition, and a foamed, defibrated molding sheet. [Means for solving the problem]

[0006] A resin composition for foam defibrillation molding according to one embodiment of the present invention contains a polycarboxylic acid ester (A) and a polycarboxylic acid ester (B). The melt flow rate (MFR) of the polycarboxylic acid ester (A) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(A)), and the melt flow rate (MFR) of the polycarboxylic acid ester (B) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(B)), wherein MFR(A) is greater than MFR(B), and MFR(A) and MFR(B) satisfy the MFR ratio shown in the following formula (I): (I) Formula 1.3≦ MFR(A) / MFR(B)≦100

[0007] Another embodiment of the present invention provides a foamed, defibrated molding comprising a polycarboxylic acid ester (A) and a polycarboxylic acid ester (B). The melt flow rate (MFR) of the polycarboxylic acid ester (A) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(A)), and the melt flow rate (MFR) of the polycarboxylic acid ester (B) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(B)), wherein MFR(A) is greater than MFR(B), and MFR(A) and MFR(B) satisfy the MFR ratio represented by the following formula (I): (I) Formula 1.3≦ MFR(A) / MFR(B)≦100

[0008] A method for molding a foamed and defibrated molding according to another embodiment of the present invention includes the steps of extruding the resin composition for foamed and defibrated molding to obtain an extrudate, the resin composition containing a blowing agent in an amount of 0.2 parts by mass or more and 10 parts by mass or less, when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is taken as 100 parts by mass, and foaming and defibrating the extrudate.

[0009] Another embodiment of the present invention is a foamed defibrated sheet comprising a polycarboxylic acid ester, wherein the polycarboxylic acid ester has a weight average molecular weight of 10,000 or more and 1,000,000 or less, and the foamed defibrated sheet has an average thickness of 100 μm or more and 500 μm or less, and a portion that is not defibrated or perforated in the transverse direction (TD) of 5 mm or more is 100 cm 2 There is no fiber or hole in the width direction (TD) of 100cm. 2 It is a foam defibrillation sheet with less than five holes. [Effects of the Invention]

[0010] The present invention can provide a resin composition that can produce foamed, defibrated moldings with denser fibers and more uniform bubbles, a foamed, defibrated molding produced from the resin composition, and a method for molding a foamed, defibrated molding using the resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1. First embodiment The first embodiment of the present invention relates to a resin composition for foam defibration molding. The resin composition contains at least two polycarboxylic acid esters with different melt flow rates (MFR). The MFR (MFR(A)) of one of the polycarboxylic acid esters, polycarboxylic acid ester (A), is greater than the MFR (MFR(B)) of another of the polycarboxylic acid esters, polycarboxylic acid ester (B), and MFR(A) and MFR(B) satisfy the MFR ratio shown in the following formula (I). These polycarboxylic acid esters with different MFRs are not completely compatible during melt-kneading, and it is believed that the polycarboxylic acid ester with the smaller MFR is finely dispersed in the polycarboxylic acid ester with the larger MFR. It is believed that this facilitates the generation of finer and more uniform bubbles at the interface between these polycarboxylic acid esters, thereby enabling the formation of finer and more uniform fibers. (I) Formula 1.3≦ MFR(A) / MFR(B)≦100

[0012] From the above viewpoints, the MFR ratio between the polycarboxylic acid esters is 1.3 or more, preferably 1.5 or more, more preferably 2 or more, and even more preferably 5 or more. When the resin composition contains three or more polycarboxylic acid esters with different MFRs, the MFR ratio between the polycarboxylic acid esters with the smallest MFR ratio should be within the above range. The maximum value of the MFR ratio is preferably 80, more preferably 50, and even more preferably 10, from the viewpoints of suppressing a decrease in the elongation, impact resistance, and fluidity during production of the foamed, defibrated molding.

[0013] The polycarboxylic acid ester is a polymer having an ester structure in the main chain, which can be obtained by the polycondensation reaction of a hydroxycarboxylic acid, or the polycondensation reaction of a polycarboxylic acid and a polyol, or the polycondensation reaction of a hydroxycarboxylic acid, a polycarboxylic acid, and a polyol. The polycarboxylic acid ester may have only structural units derived from a hydroxycarboxylic acid, or only structural units derived from a polycarboxylic acid and a polyol, or may have all structural units derived from a hydroxycarboxylic acid, a polycarboxylic acid, and a polyol in the molecule. The polycarboxylic acid ester may also have structural units derived from monomers other than these.

[0014] The hydroxycarboxylic acid is a compound having a carboxyl group and a hydroxy group in the molecule. Examples of hydroxycarboxylic acids that can be used in the synthesis of the polycarboxylic acid ester include lactic acid, glycolic acid, hydroxybutyric acid, hydroxypentanoic acid, hydroxycaproic acid, and hydroxyheptanoic acid, as well as derivatives thereof, lactones (such as ε-caprolactone and δ-valerolactone) that undergo intramolecular dehydration condensation, and compounds such as lactide and glycolide that undergo intermolecular dehydration condensation. The lactic acid may be either L-lactic acid or D-lactic acid, or both may be used.

[0015] The polycarboxylic acid may be a dicarboxylic acid or a tricarboxylic or higher carboxylic acid, but is preferably a dicarboxylic acid. Examples of the polycarboxylic acid include saturated polycarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, malic acid, tartaric acid, dodecanedioic acid, and citric acid, as well as unsaturated polycarboxylic acids such as fumaric acid, maleic acid, itaconic acid, and citraconic acid.

[0016] The polyol may be a dihydric diol or a trihydric or higher polyol, but a dihydric diol is preferred. Examples of the diol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol-polypropylene glycol copolymer, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, polytetramethylene glycol, glycerin, and trimethylolpropane.

[0017] Examples of the polycarboxylic acid ester include polymers containing structural units derived from lactic acid, or may contain both structural units derived from lactic acid and structural units derived from a hydroxycarboxylic acid other than lactic acid. Furthermore, the polymer may contain both structural units derived from lactic acid and structural units derived from glycolic acid or hydroxycaproic acid. Preferably, the polymer is composed essentially of structural units derived from lactic acid. "Substantially" means that the amount of structural units derived from a hydroxycarboxylic acid, polycarboxylic acid, or polyol other than lactic acid is less than 2 parts by mass relative to the total mass of the polycarboxylic acid ester.

[0018] The molecular weight of the polycarboxylic acid ester may be increased by a known coupling agent, examples of which include diisocyanates, oxazolines, diepoxy compounds, and acid anhydrides.

[0019] The polycarboxylic acid ester can be synthesized by a known method using a known catalyst, or a commercially available polycarboxylic acid ester may be used.

[0020] The polycarboxylic acid ester may be a polymer of biological origin, such as polyhydroxyalkylcarboxylic acid derived from microorganisms.

[0021] The resin composition contains at least two polycarboxylic acid esters with different MFRs. Of these at least two polycarboxylic acid esters, the polycarboxylic acid ester (A) with the larger MFR has an MFR of 0.1 g / 10 min or more and 100 g / 10 min or less. The polycarboxylic acid ester (B) with the smaller MFR also has an MFR of 0.1 g / 10 min or more and 100 g / 10 min or less. However, as described above, the ratio of the MFR of the polycarboxylic acid ester (A) to the MFR of the polycarboxylic acid ester (B) is 1.3 or more.

[0022] The MFR of the polycarboxylic acid ester is measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg.

[0023] The polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) may be polymers having structural units derived from the same type of monomer, or may be polymers having structural units derived from different types of monomer. From the viewpoint of improving the degradability of foamed, defibrated moldings, it is preferable that at least one of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is a polylactic acid ester, and it is more preferable that both the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) are polylactic acid esters. Note that the polylactic acid ester refers to a polycarboxylic acid ester in which the structural unit that is most abundant on a molar basis among the structural units that constitute the polymer is a structural unit derived from lactic acid. The polylactic acid ester may have either a structural unit derived from L-lactic acid or a structural unit derived from D-lactic acid, or may have both of these structural units. Note that the simple term "amount of structural units derived from lactic acid" refers to the amount including structural units derived from L-lactic acid and structural units derived from D-lactic acid.

[0024] The polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) each preferably have a weight-average molecular weight of 50,000 or more and 2,000,000 or less. When the molecular weight is 50,000 or more, molding is easy and the strength of the foamed, defibrated molded body tends to be increased. When the molecular weight is 2,000,000 or less, melt extrusion is easy. In this specification, the weight-average molecular weight is the molecular weight measured by gel permeation chromatography (GPC) and converted into polystyrene.

[0025] The blending ratio of the polycarboxylic acid ester (A) to the polycarboxylic acid ester (B) is preferably (polycarboxylic acid ester (A) / polycarboxylic acid ester (B))=(40 / 60) or more and (60 / 40) or less. When the blending ratio is within the above range, more interfaces are formed between the two types of polycarboxylic acid esters, which can form fine and uniform cells, and therefore, a foamed defibrillation molding can be produced with denser fibers and more uniform cells.

[0026] The weight average molecular weight of the polycarboxylic acid ester is a value measured by gel permeation chromatography (GPC) and converted based on standard polystyrene.

[0027] The resin composition may contain, in addition to the polycarboxylic acid ester, known thermoplastic resins other than the polycarboxylic acid ester and additives.

[0028] The type of thermoplastic resin other than the polycarboxylic acid ester is not particularly limited, but from the viewpoint of enhancing the degradability of the foamed and defibrated molding, degradable polymers such as polyglycolic acid and poly-ε-caprolactone are preferred.

[0029] The types of the additives are not particularly limited, and known hydrolysis inhibitors, plasticizers, antioxidants, stabilizers, ultraviolet absorbers, colorants, crystallization accelerators, and the like, as well as effective substances according to the intended use of the foamed, defibrated molding, can be used.

[0030] Examples of the hydrolysis inhibitor include addition reaction type compounds such as carbodiimide compounds, isocyanate compounds, epoxy compounds, oxazoline compounds, oxazine compounds, and aziridine compounds.

[0031] The content of the hydrolysis inhibitor is preferably more than 0 parts by mass and not more than 10 parts by mass, and more preferably 0.5 parts by mass or more and not more than 5 parts by mass, when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is taken as 100 parts by mass. When the content of the hydrolysis inhibitor is 10 parts by mass or less, the moldability, mechanical strength, and various physical properties of the foamed, defibrated molding are less likely to deteriorate.

[0032] Examples of the plasticizer include fatty acid ester surfactants, phthalic acid derivatives including di-n-octyl phthalate, di-2-ethylhexyl phthalate, and dibenzyl phthalate, isophthalic acid derivatives including diisooctyl phthalate, adipic acid derivatives including di-n-butyl adipate and dioctyl adipate, maleic acid derivatives including di-n-butyl maleate, citric acid derivatives including tri-n-butyl citrate, itaconic acid derivatives including monobutyl itaconate, oleic acid derivatives including butyl oleate, ricinoleic acid derivatives including glycerin monoricinoleate, phosphate ester plasticizers including tricresyl phosphate and trixylenyl phosphate, lactic acid, linear lactic acid oligomers, cyclic lactic acid oligomers, and lactide.

[0033] The content of the plasticizer is preferably 0.1 to 20 parts by mass when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is 100 parts by mass. When the content of the plasticizer is 0.1 part by mass or more, the toughness of the foamed, defibrated molding can be increased, and the foamed, defibrated molding can be made less likely to break even when pulled while maintaining its flexibility. When the content of the plasticizer is 20 parts by mass or less, the moldability, mechanical strength, and various physical properties of the foamed, defibrated molding are less likely to deteriorate.

[0034] 2. Method for forming defibrated foam moldings The resin composition can be used to form a foamed, defibrated molding. Specifically, the foamed, defibrated molding can be formed by melt-extruding the resin composition containing a foaming agent to obtain an extrudate, and then foaming and defibrating the extrudate.

[0035] 2-1. Preparation of extrudates First, the resin composition containing a foaming agent is prepared. The foaming agent may be pre-contained in the resin composition as a chemical foaming agent, or may be added to the resin composition during melt extrusion (before or after feeding into the extruder). Alternatively, an extrudate may be produced by physical foaming, for example, by injecting a gas such as carbon dioxide or nitrogen into the cylinder of the extruder.

[0036] The foaming agent may be a known foaming agent. Examples of the foaming agent include organic foaming agents such as azo-based, hydrazine-based, triazole-based, N-nitrone-based, and citric acid; inorganic foaming agents such as sodium hydrocarbon and azides; volatile liquids such as acetone, methyl ethyl ketone, ethyl acetate, methyl chloride, ethyl chloride, chloroform, methylene chloride, and methylene bromide; and room-temperature gaseous compounds such as nitrogen, carbon dioxide, ammonia, methane, ethane, propane, ethylene, propylene, and gaseous halogenated hydrocarbons. Among these, organic foaming agents are preferred because they have sufficient foaming efficiency and are less likely to cause hydrolysis of the polycarboxylic acid ester as a side effect, and azo-based organic foams are more preferred.

[0037] The additives such as the hydrolysis inhibitor described above for the resin composition may also be added to the resin composition during melt extrusion (before or after feeding into the extruder). The amount of the additives such as the hydrolysis inhibitor added at this time may be the same as the amount described above for the resin composition.

[0038] The amount of the foaming agent in this step is preferably 0.2 parts by mass or more and 10 parts by mass or less when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is 100 parts by mass. When the amount of the foaming agent is 0.2 parts by mass or more, the resin composition can be foamed more sufficiently. When the amount of the foaming agent is 10 parts by mass or less, extrusion is easier.

[0039] The resin composition containing the foaming agent is first melt-kneaded in an extruder and then extruded through a die having a circular or linear slit, thereby forming a film-like extrudate.

[0040] The extruder may be a known single-screw extruder or a twin-screw extruder. The kneading temperature in the cylinder can be 100°C or higher and 270°C or lower, preferably 130°C or higher and 250°C or lower. The extrusion temperature from the die can also be 100°C or higher and 270°C or lower, preferably 130°C or higher and 250°C or lower. The screw rotation speed at this time is preferably 5 m / min or higher and 50 m / min or lower, more preferably 10 m / min or higher and 30 m / min or lower. The die lip opening is preferably 0.2 mm or higher and 0.6 mm or lower.

[0041] 2-2. Defibration of extruded material Next, the extrudate extruded from the die is foamed and defibrated. Specifically, the film-like extrudate immediately after extrusion is rapidly cooled by air cooling. This causes the bubbles in the extrudate to rapidly expand. The extrudate with expanded bubbles is then cooled and solidified by a casting roll. The extrudate is then taken up while applying a draft, and the expanded bubbles burst and coalesce due to the extension of the extrudate, thereby defibrating the extrudate into fibers, thereby obtaining a foamed and defibrated molding. The obtained foamed and defibrated molding may be wound up into a roll. The take-up speed is preferably 0.2 m / min to 5 m / min, more preferably 0.5 m / min to 3 m / min. The take-up speed is preferably 0.2 m / min to 5 m / min, more preferably 0.5 m / min to 3 m / min. The draft ratio is preferably 1 to 1.5, more preferably 1 to 1.2.

[0042] By the above method, it is possible to obtain a defibrated foamed molding which is an aggregate of fine fibers gathered in a network shape.

[0043] The method for defibrating the extrudate is not limited to the above-mentioned method, and may be, for example, an inflation method that does not use a casting roll. By the inflation method, a sheet-like or film-like expanded defibrated molding can be obtained.

[0044] These foamed defibrator moldings may contain the other resins described above and additives such as hydrolysis inhibitors and plasticizers. The contents of these other resins and additives in the foamed defibrator moldings are usually the same as those in the resin composition.

[0045] From the viewpoint of increasing the toughness of the foamed defibrated molding, it is preferable not to reduce the molecular weight of the polycarboxylic acid ester too much by excessive kneading during production. From the above viewpoint, in the foamed defibrated molding, it is preferable that both the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) have a weight average molecular weight of 20,000 or more and 500,000 or less. When the weight average molecular weight is 20,000 or more, the strength of the foamed defibrated molding tends to be increased. When the weight average molecular weight is 500,000 or less, the flexibility of the foamed defibrated molding tends to be increased.

[0046] When the foamed defibrated molding is a sheet-like molding, the measured weight-average molecular weight of the polycarboxylic acid ester contained in the molding (foamed defibrated molding sheet) is preferably 10,000 or more and 1,000,000 or less, and more preferably 20,000 or more and 500,000 or less. When the weight-average molecular weight is 10,000 or more, the strength of the foamed defibrated molding sheet tends to be increased. When the weight-average molecular weight is 1,000,000 or less, the flexibility of the foamed defibrated molding tends to be increased. Note that this measured value is the weight-average molecular weight of the entire multiple polycarboxylic acid esters, such as polycarboxylic acid ester (A) and polycarboxylic acid ester (B).

[0047] Furthermore, the average thickness of the sheet-like molded product is preferably 100 μm or more and 500 μm or less, more preferably 100 μm or more and 400 μm or less, and even more preferably 100 μm or more and 300 μm or less. When the average thickness is 100 μm or more, the strength of the foamed defibrated molded product tends to be increased. When the average thickness is 500 μm or less, the flexibility of the foamed defibrated molded product tends to be increased. The average thickness is the average value of thicknesses observed at any 10 points on the molded product.

[0048] The foamed defibrated molding thus produced had a basis weight of 10 g / m 2 More than 200g / m 2 Preferably, it is 20 g / m or less. 2 More than 150g / m 2 More preferably, it is 20 g / m or less.2 More than 100g / m 2 More preferably, it is 20 g / m or less. 2 More than 50g / m 2 The following is particularly preferable: The above-mentioned defibrated foamed molding can have a sufficient strength while having a low basis weight because the fibers can be made denser and the cells can be made more uniform.

[0049] Furthermore, the foamed defibrated molding (or foamed defibrated sheet) produced in this manner has a good defibrated state. Specifically, when the surface area of ​​the foamed defibrated molding (or foamed defibrated sheet) is 100 cm², 2 When observing this range, there will be no areas in the width direction (TD) that are not defibrated or perforated that are 5 mm or larger, and there will be fewer than five areas in the width direction (TD) that are not defibrated or perforated that are 2 mm or larger. The number of areas in the width direction (TD) that are not defibrated or perforated that are 2 mm or larger is preferably fewer than two. Note that this observation is preferably the average value of the results of observations at any 10 locations. In this embodiment, the fibers are made denser and the cells are made more uniform during foaming and defibration, so that an expanded defibrated molding (or expanded defibrated material sheet) with few areas that are not defibrated or perforated can be obtained.

[0050] 3. Uses of defibrated foam moldings The foamed and defibrated moldings thus obtained can be used in a variety of applications. Furthermore, because the foamed and defibrated moldings are made from polycarboxylic acid ester, they are highly biodegradable. Therefore, the foamed and defibrated moldings can be suitably used in plumbing products (kitchen and bathroom products), including kitchen and bathroom products such as draining nets and filters, absorbents for oil and other liquids, hygiene products including masks, diapers, and gauze, and gardening products including breathable mulch film, vegetation nets, young tree protection nets, and compost garbage bags. [Example]

[0051] The present invention will be described below with reference to examples, which should not be construed as limiting the scope of the present invention.

[0052] 1. Prepare ingredients 1-1. Polycarboxylic acid ester (A) "4032D" manufactured by NatureWorks LLC was used. This polycarboxylic acid ester is a polymer consisting essentially of structural units derived from lactic acid, and has a melt flow rate (MFR) of 7 g / 10 min at 210°C under a load of 2.16 kg, measured in accordance with ASTM D1238, and a weight average molecular weight (Mw) of 78,100.

[0053] 1-2. Synthesis of polycarboxylic acid ester (B) The polycarboxylic acid ester used was "H440" manufactured by Mitsui Chemicals, Inc. This polycarboxylic acid ester is a polymer consisting essentially of structural units derived from lactic acid, and has a melt flow rate (MFR) of 3.3 g / 10 min at 210°C under a load of 2.16 kg, measured in accordance with ASTM D1238, and a weight average molecular weight (Mw) of 175,100.

[0054] 1-3. Foaming agents Azodicarbonamide (ADCA), an azo-based organic blowing agent, was used.

[0055] 1-4. Hydrolysis inhibitors A carbodiimido compound was used.

[0056] 1-5. Plasticizers Tirabazole VR-17 manufactured by Taiyo Kagaku Co., Ltd. was used.

[0057] 2. Forming of defibrated foam molding The above materials were charged into an extruder in the proportions shown in Table 1, melt-kneaded at the cylinder temperature, die extrusion temperature, and cylinder rotation speed shown in Table 1, and extruded through a die with a slit to obtain a film-like extrudate.

[0058] The extrudate was air-cooled immediately after extrusion from the die, and then cooled and solidified by a casting roll at the temperature shown in Table 1. After that, while applying a draft, it was taken up by a take-up roll rotating at the rotation speed shown in Table 1, and then taken up by a take-up roll rotating at the rotation speed shown in Table 1 to obtain a foamed, defibrated molding.

[0059] 3. Evaluation The obtained foamed and defibrated moldings were evaluated according to the following criteria.

[0060] 3-1.Basic weight A sample of 5 cm square was cut from the obtained defibrated foam and weighed. 2 Converted to weight per unit, basis weight (g / m 2 ) was decided.

[0061] 3-2. Defibration state The obtained foamed and defibrated molding was observed at 10 random locations and evaluated according to the following criteria. 〇 5mm or more of fiber is opened in the transverse direction (TD), and the unopened portion is 100cm 2 There is no fiber or hole in the width direction (TD) of 100cm. 2 There are fewer than five locations within △ 5mm or more of fiber split in the transverse direction (TD), and the unopened area is 100cm 2 There is at least one puncture or puncture in the width direction (TD) of 2 mm or more, and the puncture is not open in 100 cm 2 There are five or more locations within

[0062] Table 1 shows the manufacturing conditions and evaluation results of the obtained foamed and defibrated moldings.

[0063] [Table 1]

[0064] As is clear from Table 1, when two types of polycarboxylic acid esters with different MFRs were used, it was possible to obtain foamed defibrated moldings that were lighter and in a better defibrated state. [Industrial Applicability]

[0065] The resin composition of the present invention makes it possible to produce foamed defibrillated moldings with denser fibers and more uniform cells. Therefore, the present invention is expected to further expand the applicability of foamed defibrillation molding and contribute to the further spread of foamed defibrillation molding.

Claims

1. A composition comprising a polycarboxylic acid ester (A) which is a polylactic acid ester, a polycarboxylic acid ester (B) which is a polylactic acid ester, and a hydrolysis inhibitor, the polycarboxylic acid ester (A) has a melt flow rate (MFR) of 0.1 g / 10 min or more and 100 g / 10 min or less at 210°C under a load of 2.16 kg, as measured in accordance with ASTM D1238 (hereinafter referred to as MFR(A)); the melt flow rate (MFR) of the polycarboxylic acid ester (B) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(B)); A resin composition for foam defibration molding, wherein MFR(A) is greater than MFR(B), and MFR(A) and MFR(B) satisfy the MFR ratio shown in the following formula (I): (I) Formula 1.3≦MFR(A) / MFR(B)≦100

2. A resin composition for foam defibration molding as described in claim 1, containing the hydrolysis inhibitor in an amount that is more than 0 parts by mass and not more than 10 parts by mass when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is 100 parts by mass.

3. A composition comprising a polycarboxylic acid ester (A) which is a polylactic acid ester, a polycarboxylic acid ester (B) which is a polylactic acid ester, and a hydrolysis inhibitor, the polycarboxylic acid ester (A) has a melt flow rate (MFR) of 0.1 g / 10 min or more and 100 g / 10 min or less at 210°C under a load of 2.16 kg, as measured in accordance with ASTM D1238 (hereinafter referred to as MFR(A)); the melt flow rate (MFR) of the polycarboxylic acid ester (B) measured in accordance with ASTM D1238 at 210°C under a load of 2.16 kg is 0.1 g / 10 min or more and 100 g / 10 min or less (hereinafter referred to as MFR(B)); A foamed, defibrated molding in which MFR(A) is greater than MFR(B), and MFR(A) and MFR(B) satisfy the MFR ratio shown in the following formula (I): (I) Formula 1.3≦MFR(A) / MFR(B)≦100

4. The foamed defibrated molding according to claim 3, comprising the hydrolysis inhibitor in an amount greater than 0 parts by mass and not greater than 10 parts by mass, when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is 100 parts by mass.

5. The foamed, defibrated molding according to claim 3 or 4, which is an aggregate of fine fibers.

6. The foamed, defibrated molding according to claim 3 or 4, which is in the form of a sheet or film.

7. a step of extruding the resin composition for foam defibrillation molding according to claim 1 or 2, which contains a blowing agent in an amount of 0.2 parts by mass or more and 10 parts by mass or less, when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is taken as 100 parts by mass; and and defibrating the extrudate. A method for forming a defibrated foamed molding.

8. 8. The method for molding a foamed defibrillated molding according to claim 7, wherein in the step of obtaining the extrudate, the hydrolysis inhibitor is added to the resin composition for foamed defibrillation molding in an amount that is more than 0 part by mass and not more than 10 parts by mass, when the total mass of the polycarboxylic acid ester (A) and the polycarboxylic acid ester (B) is taken as 100 parts by mass.

9. A foamed defibrated sheet comprising the resin composition for foamed defibrated molding according to claim 1 or 2, The polycarboxylic acid ester includes a polycarboxylic acid ester having a weight average molecular weight of 10,000 or more and 1,000,000 or less, the average thickness of the foamed defibrated sheet is 100 μm or more and 500 μm or less, The fiber is opened in the width direction (TD) by 5 mm or more, and the unopened portion is 100 cm ２ The part that is not defibrated or perforated in the width direction (TD) is 2 mm or more and is not present within 100 cm ２ There are fewer than five locations within Foam defibrillator sheet.

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