JP2010163497A - Polymer composition material and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a polymer composition material with improved recovery efficiency by reducing the molecular weight of natural lignin extracted from a wood-derived material. <P>SOLUTION: Natural lignin extracted from a pulverized wood-derived material is hydrolyzed by critical water treatment in a methyl ethyl ketone solvent at high temperature and pressure, the resulting product is purified to obtain a lignin derivative with reduced molecular weight, and a reaction active acid anhydride type functional group is introduced into the lignin derivative by chemical modification. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polymer composition material added to a thermosetting resin constituting electric and electronic parts and a method for producing the same.

  Conventionally, thermosetting resins such as epoxy resins and polyester resins have excellent mechanical, electrical, and thermal properties, and have been widely used as insulating structural materials constituting electrical and electronic components. However, since it has excellent durability, it has been difficult to reuse or disassemble the waste after disposal for many years. In addition, because of the harmony with the global environment, there is a need for materials that have relied on oil and added new functions.

  In response to such demands, a method is known in which epichlorohydrin and glycidyl ether are allowed to act on lignin extracted from plant biomass and epoxidized. By such a method, an insulating structure material in which carbon dioxide emission is suppressed can be obtained (for example, see Patent Document 1).

JP 2006-66237 A (pages 4-5)

  The above conventional insulating structural materials have the following problems. The lignin contained in plant-based biomass has many high molecular weights and has a very low recovery rate. In addition, the extracted lignin is a high molecular weight substance, and its molecular weight and structure vary depending on the type of wood that is the raw material. For this reason, when used after being epoxidized, it is difficult to perform a chemical addition reaction, and it is difficult to obtain an insulating structure material in which the lignin derivative is uniformly dispersed. In addition, the high molecular weight body has a high melting point, and there is a fear that handling may be reduced.

  For this reason, the lignin derivative is reduced in molecular weight to improve the recovery rate, and when added to the thermosetting resin, it uniformly disperses and binds, exhibits excellent properties as an insulating structure material, and is easy to dispose of. What was said to have been desired.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a polymer composition material obtained by reducing the molecular weight of a high molecular weight lignin derivative extracted from wood and a method for producing the same.

  In order to achieve the above object, the polymer composition material of the present invention comprises a lignin derivative obtained by hydrolyzing natural lignin by a critical water treatment, and a reactive functional group introduced into the lignin derivative by chemical modification. Features.

  According to the present invention, natural lignin is treated with critical water under high temperature and high pressure to reduce the molecular weight, and the reactive functional group is introduced by chemical modification. Therefore, the recovery efficiency of the lignin derivative can be improved, and the insulating structure Various characteristics as a material can be improved, and reuse and decomposition can be facilitated even in disposal.

The conceptual diagram explaining the manufacturing method of the polymeric composition material which concerns on this invention. Process drawing explaining the manufacturing method of the polymeric composition material which concerns on the Example of this invention. The figure explaining the molecular weight of the lignin of the polymer composition material which concerns on the Example of this invention.

  A method for producing the polymer composition material will be described with reference to FIG. As shown in FIG. 1, first, the wood-derived material is dried and pulverized (st1). Next, it is hydrolyzed with supercritical water or subcritical water to lower the molecular weight of the lignin derivative (st2). The precipitate is removed from the turbid solution, and the lignin derivative having a reduced molecular weight is separated and purified from the solution (st3). Next, a reactive functional group is introduced into the lignin derivative and reacted (st4). When this is purified, a polymer composition material having a lignin derivative reduced in molecular weight can be obtained. Examples of the present invention will be described below.

  A polymer composition material according to an embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a process diagram illustrating a method for producing a polymer composition material according to an embodiment of the present invention, and FIG. 3 is a diagram illustrating a molecular weight of lignin of the polymer composition material according to an embodiment of the present invention.

  As shown in FIG. 2, corn cob is used as the wood-derived material, and is first dried and pulverized to a particle size of several tens of μm (st11). Thereby, a high molecular weight natural lignin is obtained. Natural ligging is subjected to critical water treatment at a temperature of 180 ° C. and a pressure of 1.8 MPa in a water-methyl ethyl ketone mixed solvent in the presence of a metal catalyst (st12). Thereby, lignin is hydrolyzed, and when this is dried, separated, and purified, lignin reduced in molecular weight can be obtained (st13).

  As the solvent, in addition to methyl ethyl ketone, at least one of methanol, ethanol, propanol, acetone, diethyl ether, dioxane, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, acetic acid, and butyric acid can be used.

  Here, the reduction in molecular weight is to move the molecular weight distribution toward the low molecular weight side as shown by the solid line with respect to the natural lignin shown by the dotted line as shown in FIG. By reducing the molecular weight, the lignin derivative can be efficiently recovered. In addition, the molecular weight is equal to or less than that of a thermosetting resin such as an epoxy resin described later. Equivalent means taking into account variations such as when manufacturing materials or mixing materials.

  The critical water treatment is to pressurize the turbid liquid and cause it to react with the liquid in a high temperature state and the object (lignin). Can do. If the turbid liquid is a critical water having a temperature of 180 ° C. or higher and a pressure of 1.8 MPa or higher, the turbid liquid will evaporate in the vessel that decomposes lignin, but is pressurized and mixed with high-temperature liquid and lignin. Low molecular weight can be efficiently achieved. Furthermore, when the turbid liquid is acidified to pH 6 or less, the decomposition of lignin can be accelerated.

Next, when an acid anhydride such as trimellitic anhydride is chemically modified, a functional group (a 5-membered ring made of an acid anhydride) can be introduced into the hydroxyl group terminal of the low molecular weight lignin by a dehydration reaction. (St14). See [Chemical Formula 1]. Thereby, a polymer composition material having a lignin derivative having a reduced molecular weight can be obtained in a powder or liquid state.

  The lignin derivative having a reduced molecular weight includes at least one of functional groups such as an epoxy group, an amide group, an amine group, an imidazole group, a carboxyl group, a vinyl group, and an alkoxide group in addition to an acid anhydride functional group. More than one type can be introduced into the molecular structure. These functional groups activate bonds with the thermosetting resin and are defined as reactive functional groups.

  When a polymer composition material is mixed with an epoxy resin typified by a thermosetting resin and cured (st15), the lignin derivative is uniformly dispersed and bonded to the epoxy resin, and has excellent mechanical, electrical, A biomass-based insulating structural material having various thermal characteristics can be obtained. The lignin derivative is a carbon neutral material, and can be easily reused and decomposed in the disposal of the waste of the insulating structure material.

  In addition, since it has a lower molecular weight than conventional natural lignin, it has a low melting point, can suppress an increase in viscosity when added to a thermosetting resin, and improves handling during the production of insulating structural materials. be able to.

  According to the polymer composition material of the above example, natural lignin was subjected to high-temperature and high-pressure critical water treatment in a mixed solvent of water and methyl ethyl ketone to reduce the molecular weight, and an acid anhydride functional group was introduced by chemical modification. Therefore, the recovery efficiency of the lignin derivative can be improved. In addition, the lignin derivative is uniformly dispersed when bonded to the thermosetting resin, and can be an insulating structural material having excellent mechanical, electrical, and thermal properties. Also in the disposal of these, reuse and decomposition can be facilitated.

Claims (6)

A lignin derivative obtained by hydrolyzing natural lignin by critical water treatment;
A polymer composition material comprising a reactive functional group introduced into the lignin derivative by chemical modification.   The polymer composition material according to claim 1, wherein the lignin derivative has a molecular weight equal to or less than a molecular weight of a thermosetting resin. Extract natural lignin from wood-derived materials,
This natural lignin is treated with critical water in at least one solvent of methyl ethyl ketone, methanol, ethanol, propanol, acetone, diethyl ether, dioxane, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, acetic acid and butyric acid. And
Next, the turbid solution is purified to obtain a low molecular weight lignin derivative,
A method for producing a polymer composition material, wherein a reactive functional group is introduced into this lignin derivative by chemical modification.   The reactive functional group is at least one or more of functional groups of acid anhydride functional groups, epoxy groups, amide groups, amine groups, imidazole groups, carboxyl groups, vinyl groups, and alkoxide groups. The method for producing a polymer composition material according to claim 3.   The method for producing a polymer composition material according to claim 3 or 4, wherein the turbid liquid is boiled and pressurized.   The method for producing a polymer composition material according to any one of claims 3 to 5, wherein the turbid liquid is made acidic.

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