JP2006176648A - Antistatic agent for biodegradable resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antistatic agent for a biodegradable resin capable of exhibiting antistatic performance at a small addition level without impeding biodegradability of the biodegradable resin. <P>SOLUTION: This antistatic agent for a biodegradable resin comprises at least one kind selected from quaternary ammonium salt expressed by general formula(1), where R<SP>1</SP>represents an 8-22C alkyl group or the like; R<SP>2</SP>represents a 1-22C alkyl group or a group expressed by the formula: -(R<SP>5</SP>O)<SB>m</SB>H; R<SP>3</SP>represents a 1-2C alkyl group or a group expressed by the formula: -(R<SP>6</SP>O)<SB>n</SB>H; R<SP>4</SP>represents a 1-2C alkyl group; X- represents ClO<SB>4</SB><SP>-</SP>or R<SP>7</SP>SO<SB>4</SB><SP>-</SP>; R<SP>5</SP>and R<SP>6</SP>each represent a 2-3C alkylene group; m and n each denote a number of 1-10; and R<SP>7</SP>represents a 1-2C alkyl group. This biodegradable resin composition comprises the antistatic agent and a biodegradable resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an antistatic agent for a biodegradable resin, and a biodegradable resin composition having excellent heat resistance and antistatic properties.

  General-purpose resins made from petroleum such as polyethylene, polypropylene, polyvinyl chloride, and polystyrene are lightweight and have good processability, physical properties, and durability. Used in various fields such as building materials and food packaging. However, these resin products have a disadvantage of good durability at the stage of finishing the function and are discarded, and are inferior in degradability in nature, and thus may affect the ecosystem.

  In order to solve such problems, as a polymer having a biodegradability with a thermoplastic resin, polylactic acid, a copolymer of lactic acid and another aliphatic hydroxycarboxylic acid, an aliphatic polyhydric alcohol and an aliphatic polyvalent carboxylic acid are used. Biodegradable resins such as aliphatic polyesters derived from acids and copolymers containing these units have been developed.

  When these biodegradable resins are placed in soil, seawater, or in the body of an animal, they start to degrade in a few weeks due to the action of enzymes produced by naturally occurring microorganisms. Disappears in between. Furthermore, the decomposition products become lactic acid, carbon dioxide, water, etc., which are harmless to the human body. Among the biodegradable resins, polylactic acid resin (PLA) is a low-cost product of L-lactic acid made from saccharides obtained from corn, straw, etc. by fermentation. Since the amount of polymer obtained is extremely small and the performance of the polymer obtained is characterized by high rigidity and transparency, it is expected to be used today, and agricultural civil engineering such as flat yarn, nets, horticultural materials, seedling pots, etc. Used in the field of materials, envelopes with windows, shopping bags, compost bags, stationery, miscellaneous goods, etc. Further, in the case of polylactic acid resin, application development to films and sheets has been actively performed by utilizing the fact that transparency is very good. However, biodegradable resins, like petroleum-based plastics, are easily charged, and have the disadvantage of deteriorating the appearance due to the adhesion of dust and dust. Furthermore, plasticizers and the like are added to polylactic acid resins, and development into semi-rigid and soft materials is also actively performed. However, charging is similarly caused, and imparting antistatic ability is an indispensable situation.

  Various methods of adding an antistatic agent to impart an antistatic function to biodegradable resins such as polylactic acid resins have been proposed. For example, a method of adding a glycerin mono fatty acid ester (Patent Document 1), a method of using a glycerin mono fatty acid ester and an alkyl sulfonate together (Patent Document 2), a method of adding a nonionic antistatic agent (Patent Document 3), etc. There is. In Patent Document 3, a composition in which a quaternary ammonium salt is added instead of a nonionic antistatic agent is described as a comparative example.

However, these antistatic agents require many additions in order to obtain a good antistatic effect, deviating from the viewpoint of biodegradation, which is the original purpose of the biodegradable resin, and are difficult to apply in practice. Is the current situation.
JP 10-36650 A Japanese Patent Laid-Open No. 2004-67801 JP 2002-114900 A

  An object of the present invention is to provide an antistatic agent for a biodegradable resin that can exhibit an antistatic ability with a low addition amount without interfering with the biodegradability of the biodegradable resin, as well as excellent heat resistance and good antistatic properties. An object of the present invention is to provide a biodegradable resin composition having a function.

  The present invention relates to an antistatic agent for a biodegradable resin containing at least one selected from quaternary ammonium salts represented by general formula (1) (hereinafter referred to as quaternary ammonium salt (1)), Provided is a biodegradable resin composition containing a degradable resin and the antistatic agent.

[Wherein, R ¹ is an alkyl group or alkenyl group having 8 to 22 carbon atoms, R ² is an alkyl group having 1 to 22 carbon atoms, or a (poly) oxyalkylene group represented by the formula — (R ⁵ O) _m H , R ³ is an alkyl group having 1 to 2 carbon atoms or a (poly) oxyalkylene group represented by the formula — (R ⁶ O) _n H, R ⁴ is an alkyl group having 1 to 2 carbon atoms, and X ⁻ is ClO _4. ^- or R ⁷ SO ₄ ^- indicates, R ⁵ and R ⁶ each independently represents an alkylene group having 2 to 3 carbon atoms, m and n are each independently 1 to 10 showing an average addition mole number of the oxyalkylene group A plurality of R ⁵ and R ⁶ may be the same or different. R ⁷ represents an alkyl group having 1 to 2 carbon atoms. ]

  The antistatic agent of the present invention can impart a good antistatic ability to a biodegradable resin, and a good antistatic effect can be obtained with a low addition amount, so that it has little influence on biodegradability. In addition, the biodegradable resin composition of the present invention has excellent heat resistance, antistatic properties and transparency, and can supply sheets, films, molded articles and the like excellent in biodegradability.

[Antistatic agent]
The antistatic agent of the present invention contains at least one selected from quaternary ammonium salts (1).

In General formula (1), R < ¹ > is a C8-C22 alkyl group or an alkenyl group, and a C8-C18 alkyl group is preferable. R ² is an alkyl group having 1 to 22 carbon atoms or a (poly) oxyalkylene group represented by the formula — (R ⁵ O) _m H; R ³ is an alkyl group having 1 to 2 carbon atoms or the formula — (R ⁶ O ) A (poly) oxyalkylene group represented by _n H, wherein R ² is a (poly) oxyalkylene group represented by the formula — (R ⁵ O) _m H, and R ³ is a formula — (R ⁶ O). A (poly) oxyalkylene group represented by _n H is preferred, R ² is a (poly) oxyethylene group represented by the formula — (CH ₂ CH ₂ O) _m H, and R ³ is a formula — (CH ₂ CH ₂ O) represented by _n H (poly) oxyethylene group, what is more preferably m + n is 2-10. X ^- is ClO ₄ ^- or R ⁷ SO ₄ ^- indicates, from the viewpoint of expressing a better antistatic _{^{effect, ClO 4 -, C 2 H}} 5 SO 4 - are preferable, ClO ₄ ^- is more preferred.

  In the present specification, the (poly) oxyalkylene group means an oxyalkylene group or a polyoxyalkylene group.

  Specific examples of the quaternary ammonium salt (1) include dihydroxyethyl methyl lauryl ammonium perchlorate, dihydroxyethyl methyl cocoalkyl ammonium perchlorate, trimethyl lauryl ammonium perchlorate, dimethyl dilauryl ammonium perchlorate, dimethyl distearyl ammonium perchlorate. , Trimethyl stearyl ammonium perchlorate, hydroxyethyl dimethyl lauryl ammonium perchlorate, dipolyoxyethylene (EO = 4) methyl stearyl ammonium perchlorate, dimethyl ethyl lauryl ammonium etsulfate, dimethyl ethyl cocoalkyl ammonium etsulfate, dihydroxyethyl ethyl lauryl ammonium Etosulfate, Jihi B such carboxyethyl ethyl cocoalkyl ethosulfate, and the like, from the viewpoint of exhibiting a better antistatic effect, dihydroxyethyl methyl ammonium lauryl perchlorate, dihydroxyethyl laurylamine ethosulfate are preferable.

  The quaternary ammonium salt (1) is more preferably a compound represented by the general formula (2) from the viewpoint of developing a better antistatic effect.

[Wherein, R ¹ , R ⁴ and X ⁻ represent the above-mentioned meanings, and m 1 and n 1 are each a number of 1 or more indicating the average number of added moles of oxyethylene groups, and m 1 + n 1 = 2 to 10. ]
The quaternary ammonium salt (1) can be used alone or in combination.

The production method of the quaternary ammonium salt (1) of the present invention is not particularly limited. For example, the compound in which X ⁻ is ClO ₄ ^— is represented by the general formula (3)

(In the formula, R ¹ , R ² and R ³ have the above-mentioned meanings.)
Can be produced by adding a perchlorate and reacting with the quaternized compound with methyl chloride or ethyl chloride. A compound in which X ⁻ is R ⁷ SO ₄ ⁻ (R ⁷ has the above meaning) is produced by quaternizing the compound represented by the general formula (3) with diethyl sulfate or dimethyl sulfate. can do.

  In addition to the quaternary ammonium salt (1), the antistatic agent of the present invention includes unreacted components in the production of the quaternary ammonium salt (1) and glycerin monostearate other than the quaternary ammonium salt (1). An antistatic agent such as N, N-bishydroxyethylalkylamine can be contained.

  The content of the quaternary ammonium salt (1) in the antistatic agent of the present invention is preferably 50% by weight or more, more preferably 70% by weight or more from the viewpoint of achieving the object of the present invention. More preferably, it is 90% by weight or more.

[Biodegradable resin]
The biodegradable resin used in the present invention has a biodegradability based on JIS K6953 (ISO 14855) “Aerobic and ultimate biodegradability and disintegration test under controlled aerobic compost conditions”. The polyester resin which has is preferable.

  The biodegradable resin used in the present invention is not particularly limited as long as it has a biodegradability capable of being decomposed into a low molecular weight compound with the participation of microorganisms in nature. For example, aliphatic polyesters such as polyhydroxybutyrate, polycaprolactone, polybutylene succinate, polybutylene succinate / adipate, polyethylene succinate, polylactic acid resin, polymalic acid, polyglycolic acid, polydioxanone, poly (2-oxetanone) Aliphatic aliphatic copolyesters such as polybutylene succinate / terephthalate, polybutylene adipate / terephthalate, polytetramethylene adipate / terephthalate; starch, cellulose, chitin, chitosan, gluten, gelatin, zein, soy protein, collagen, keratin, etc. And a mixture of the above natural polymer and the above aliphatic polyester or aliphatic aromatic copolyester.

  Of these, aliphatic polyesters are preferable from the viewpoint of processability, economy, and availability in large quantities, and polylactic acid resins are more preferable from the viewpoint of physical properties. Here, the polylactic acid resin is polylactic acid or a copolymer of lactic acid and hydroxycarboxylic acid. Examples of the hydroxycarboxylic acid include glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxypentanoic acid, hydroxycaproic acid, hydroxyheptanoic acid and the like, and glycolic acid and hydroxycaproic acid are preferable. The molecular structure of polylactic acid is preferably composed of 20 to 100 mol% of either L-lactic acid or D-lactic acid and 0 to 80 mol% of each enantiomer. The copolymer of lactic acid and hydroxycarboxylic acid is composed of 85 to 100 mol% of either L-lactic acid or D-lactic acid and 0 to 15 mol% of hydroxycarboxylic acid units. These polylactic acid resins can be obtained by dehydrating polycondensation using L-lactic acid, D-lactic acid and hydroxycarboxylic acid as a raw material by selecting those having the required structure. Preferably, it can be obtained by ring-opening polymerization by selecting a desired structure from lactide, which is a cyclic dimer of lactic acid, glycolide, which is a cyclic dimer of glycolic acid, and caprolactone. Lactide includes L-lactide which is a cyclic dimer of L-lactic acid, D-lactide which is a cyclic dimer of D-lactic acid, meso-lactide obtained by cyclic dimerization of D-lactic acid and L-lactic acid, and D-lactide. There is DL-lactide, which is a racemic mixture of lactide and L-lactide. Any lactide can be used in the present invention. However, the main raw material is preferably D-lactide or L-lactide.

  Among the polylactic acid resins, from the viewpoint of heat resistance, a crystal having an optical purity of 90% or more and a ratio of crystalline polylactic acid having an optical purity of 90% or more and polylactic acid having an optical purity of less than 90% by weight is preferable. Polylactic acid / polylactic acid having an optical purity of less than 90% = 100/0 to 10/90, preferably 100/0 to 25/75.

  Examples of commercially available biodegradable resins include DuPont, trade name Biomax; BASF, trade name Ecoflex; Eastman Chemicals, trade name EsterBio; Showa Polymer Co., Ltd., trade name Bionore; Nippon Synthetic Chemical Industry Co., Ltd., trade name: Matterby; Mitsui Chemicals, Inc., trade name: Lacia; Nippon Shokubai Co., Ltd., trade name: Lunare; Chisso Corporation, trade name: Novon; Cargill Dow Polymers A product name, Nature Works, etc. are mentioned.

  Among these, preferably a polylactic acid resin (for example, trade name Lacia H-100, H-280, H-400, H-440, manufactured by Mitsui Chemicals, Inc .; trade name, Nature Works, manufactured by Cargill Dow Polymers). ), Aliphatic polyesters such as polybutylene succinate (product name Bionore, manufactured by Showa Polymer Co., Ltd.), aliphatic aromatic copolyesters such as poly (butylene succinate / terephthalate) (trade name Bio, manufactured by DuPont) Max).

[Biodegradable resin composition]
The biodegradable resin composition of the present invention contains the antistatic agent of the present invention and a biodegradable resin. The content of the antistatic agent of the present invention is preferably 0.05 to 2 parts by weight, more preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the biodegradable resin, from the viewpoint of antistatic properties and biodegradability retention. 0.6 parts by weight.

  The content of the biodegradable resin in the biodegradable resin composition of the present invention is preferably 50% by weight or more, more preferably 70% by weight or more from the viewpoint of achieving the object of the present invention.

  The composition of the present invention can contain other components such as a plasticizer and a lubricant in addition to the antistatic agent. Examples of the plasticizer include acetylated tributyl citrate and triacetin. Examples of the lubricant include hydrocarbon waxes such as polyethylene wax, and stearic acid. Further, other components such as antifogging agents, light stabilizers, ultraviolet absorbers, pigments, inorganic fillers, antifungal agents, antibacterial agents, foaming agents, flame retardants and the like are contained within a range that does not hinder the achievement of the object of the present invention. be able to.

  The method for molding the biodegradable resin composition of the present invention is not particularly limited, and can be molded by injection molding, extrusion T-die film formation, stretching, or the like by ordinary methods. There is no restriction | limiting also in the molded article use of the composition of this invention, It can apply to molded articles, such as a film and a sheet | seat.

Examples 1-4 and Comparative Examples 1-5
As a biodegradable resin, Lacia H-280 (polylactic acid resin manufactured by Mitsui Chemicals, Inc.) was used, and after vacuum drying at 50 ° C. for 12 hours to prevent hydrolysis during processing, Predetermined amounts of the present invention and comparative antistatic agents shown were added and kneaded at 150 ° C. in a kneader. The kneaded product was taken out, pulverized, and processed into a 1 mm thick sheet with an extrusion T-die machine heated to 180 ° C. Using this sheet, antistatic properties, transparency and heat resistance were evaluated by the following methods. The results are shown in Table 1.

<Antistatic evaluation method>
About the sheet | seat, the half-life of the charged voltage was measured in the room | chamber interior adjusted to 25 degreeC and 50% of humidity. As a measuring instrument, an S-5109 type static one meter (manufactured by Sisid Electric Co., Ltd.) was used.

<Transparency evaluation method>
The sheet was pressed at 150 ° C. to obtain a flat 1 mm pressure sheet. The haze value of the obtained sheet piece was measured using an integrating sphere light transmittance measuring device (haze meter) defined in JIS-K7105. The smaller this value, the better the transparency.

<Evaluation method of heat resistance>
The sheet was heated in an oven heated to 180 ° C. for 1 hour, and the color change was measured with a spectral color / white meter (PF10 type, manufactured by Nippon Denshoku Industries Co., Ltd.), and the b values were compared.

Claims (5)

An antistatic agent for a biodegradable resin containing at least one selected from quaternary ammonium salts represented by the general formula (1).

[Wherein, R ¹ is an alkyl group or alkenyl group having 8 to 22 carbon atoms, R ² is an alkyl group having 1 to 22 carbon atoms, or a (poly) oxyalkylene group represented by the formula — (R ⁵ O) _m H , R ³ is an alkyl group having 1 to 2 carbon atoms or a (poly) oxyalkylene group represented by the formula — (R ⁶ O) _n H, R ⁴ is an alkyl group having 1 to 2 carbon atoms, and X ⁻ is ClO _4. ^- or R ⁷ SO ₄ ^- indicates, R ⁵ and R ⁶ each independently represents an alkylene group having 2 to 3 carbon atoms, m and n are each independently 1 to 10 showing an average addition mole number of the oxyalkylene group A plurality of R ⁵ and R ⁶ may be the same or different. R ⁷ represents an alkyl group having 1 to 2 carbon atoms. ] The biodegradable oil-based antistatic agent according to claim 1, wherein the quaternary ammonium salt represented by the general formula (1) is a compound represented by the general formula (2).

[Wherein R ¹ , R ⁴ and X ⁻ represent the same meaning as in claim 1, and m 1 and n 1 are each a number of 1 or more indicating the average number of added moles of oxyethylene groups, and m 1 + n 1 = 2 to 10 is there. ]   A biodegradable resin composition comprising a biodegradable resin and the antistatic agent according to claim 1 or 2.   The biodegradable resin composition according to claim 3, wherein the content of the antistatic agent is 0.05 to 2 parts by weight with respect to 100 parts by weight of the biodegradable resin. The biodegradable resin composition according to claim 3 or 4, wherein the biodegradable resin is polylactic acid.