JP2015183133A - Resin composition and resin molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant resin composition that provides moldability in molding a resin molding and excellent surface impact resistance of the molding; and a flame-retardant resin molding excellent in surface impact resistance.SOLUTION: A resin composition comprises a cellulosic resin, magnesium hydroxide, and a liquid flame retardant. A resin molding comprises a cellulosic resin, magnesium hydroxide, and a liquid flame retardant.

Description

  The present invention relates to a resin composition and a resin molded body.

  Conventionally, various resin compositions have been provided, and thermoplastic resins are also used in parts such as home appliances and various parts of automobiles, casings, office equipment, and casings of electronic and electrical equipment. Plant-based resins are used as one type of resin composition, and cellulose is one of the conventionally known plant-based resins.

  For example, Patent Document 1 discloses a cellulose resin composition containing a cellulose ether ester having a hydrocarbon group and an aliphatic acyl group having 7 to 18 carbon atoms, and an inorganic salt containing an alkali metal or an alkaline earth metal. It is disclosed.

  Patent Document 2 includes a thermoplastic resin containing a cellulose-based resin and a flame retardant, and the flame retardant is a first magnesium hydroxide having a particle size of 10 nm to 50 nm whose particle surface is modified by an epoxy-based silane coupling agent. The second magnesium hydroxide particles having a particle size of 100 nm to 1000 nm whose particle surface is modified with an amino-based silane coupling agent containing 40 wt% to 60 wt% of the total flame retardant, and 60 wt% of the total flame retardant To 40% by weight of a flame retardant resin composition is disclosed.

  Patent Document 3 includes a thermoplastic resin containing a cellulose resin and a flame retardant, and 40 to 60% by weight of the entire flame retardant is modified with an epoxy silane coupling agent on the particle surface. The particle size of 10 nm is composed of particles of the first metal hydroxide having a particle size of 100 nm to 1000 nm and the surface of the flame retardant is modified by 60% to 40% by weight of an amino silane coupling agent. To 50 nm of a flame retardant resin composition composed of second metal hydroxide particles.

JP 2010-241848 A JP 2011-195722 A JP 2012-207105 A

  An object of the present invention is to provide a flame-retardant resin composition that is excellent in moldability when molding a resin molded body and surface impact resistance when formed into a molded body.

The above object is achieved by the present invention described below.
That is, the invention according to claim 1
A resin composition comprising a cellulose resin, magnesium hydroxide, and a liquid flame retardant.

The invention according to claim 2
2. The resin composition according to claim 1, wherein a content of the magnesium hydroxide is 5% by mass or more and 50% by mass or less with respect to the cellulose resin.

The invention according to claim 3
3. The resin composition according to claim 1, wherein a content of the liquid flame retardant is 1% by mass or more and 30% by mass or less with respect to the cellulose resin.

The invention according to claim 4
A resin molded body containing a cellulose resin, magnesium hydroxide, and a liquid flame retardant.

The invention according to claim 5
5. The resin molded body according to claim 4, wherein a content of the magnesium hydroxide is 5% by mass or more and 50% by mass or less with respect to the cellulose resin.

The invention according to claim 6
6. The resin molded body according to claim 4, wherein a content of the liquid flame retardant is 1% by mass or more and 30% by mass or less with respect to the cellulose resin.

The invention according to claim 7 provides:
The resin molded product according to any one of claims 4 to 6, wherein the resin composition according to any one of claims 1 to 3 is molded at a temperature of 230 ° C or higher and 260 ° C or lower. It is.

  According to the first to third aspects of the invention, compared to the case where magnesium hydroxide and the liquid flame retardant are not used in combination, the moldability when molding the resin molded body and the surface impact resistance when the molded body is formed. A flame retardant resin composition having excellent resistance is provided.

  According to the invention which concerns on Claims 4-6, compared with the case where magnesium hydroxide and a liquid flame retardant are not used together, the flame-retardant resin molding which is excellent in surface impact resistance is provided.

  According to the invention which concerns on Claim 7, the flame-retardant resin molding which is excellent in surface impact resistance compared with the case where the temperature in the case of shaping | molding is outside the said range is provided.

It is a graph which shows the result of the viscoelasticity measurement performed about the Example. It is a graph which shows the result of the viscoelasticity measurement performed about the comparative example.

  Hereinafter, embodiments of the resin composition and the resin molded body of the present invention will be described.

≪Resin composition≫
The resin composition according to the present embodiment includes a cellulose resin, magnesium hydroxide, and a liquid flame retardant.

In a resin composition containing a cellulose resin, it is known to add an inorganic filler or the like in order to improve flame retardancy, but a large amount of inorganic filler must be added in order to obtain flame retardancy. When a large amount of inorganic filler is contained, moldability (fluidity) when molding a resin molded body and mechanical strength when formed into a molded body may be lowered.
In addition, when an inorganic filler containing an alkali component is added to the cellulose resin, thermal strength of the cellulose resin is generated, and the mechanical strength and moldability (fluidity) may be reduced due to a decrease in viscosity accompanying a decrease in molecular weight. .

On the other hand, the resin composition according to the present embodiment has excellent moldability (flow) when molding a resin molded article by using magnesium hydroxide and a liquid flame retardant together with a resin composition containing a cellulose resin. Property) and excellent surface impact resistance when formed into a molded product, and excellent flame retardancy can also be achieved.
The mechanism by which this effect is achieved is not necessarily clear, but is presumed as follows.

In the cellulose resin, the liquid flame retardant is presumed to form a sea-island structure with a micro size, and since the liquid flame retardant forming the island exists in a liquid state, it is considered that the liquid flame retardant responds flexibly to deformation. Magnesium hydroxide added to the cellulose resin together with the liquid flame retardant is presumed to be present in the island-like liquid flame retardant, thereby providing flexibility against deformation and improving surface impact resistance. It seems to be.
Magnesium hydroxide coexists with the liquid flame retardant, and as the temperature rises, it appears that it reacts with the cellulose resin to cause a crosslinking reaction. Therefore, it is considered that the flame retardancy is improved by the crosslinked structure formed by the reaction.

  Charging by dehydration, decarbonation, and carbonization is performed by the action of flame retardant when the resin molding is burned, but even if char is formed, if the resin itself has fluidity, char will crack or peel off and molding It is considered that no char is formed on the body surface evenly. In contrast, in the present embodiment, as described above, it is considered that a crosslinking reaction between magnesium hydroxide and the cellulose resin occurs, thereby suppressing fluidity in a high temperature environment. As a result, it is considered that cracking and peeling of the formed char are suppressed and excellent flame retardancy is achieved.

  In addition, according to the present embodiment, flame retardancy and surface impact resistance are efficiently achieved as described above, and compared with the case of adding an inorganic filler such as magnesium hydroxide without using a liquid flame retardant together, The amount of magnesium oxide added can be reduced. Therefore, the viscosity at the time of shape | molding a resin molding is suppressed, and the outstanding moldability (fluidity) is implement | achieved.

Loss tangent (tan δ)
From the viewpoint of excellent flame retardancy, the resin composition and the resin molded body according to this embodiment have a loss tangent (Tanδ) of 1 or less under the conditions of a frequency of 6.28 rad / sec and a temperature of 250 ° C. It is preferable.

  Here, the loss tangent (tan δ) is a ratio (G ″ / G ′) between the storage elastic modulus (G ′) corresponding to elasticity and the loss elastic modulus (G ″) corresponding to viscosity, that is, the loss tangent. The larger (tan δ), the more dominant the viscosity, and the smaller (tan δ), the more dominant the elasticity. In this embodiment, the loss tangent (tan δ) under the conditions of a frequency of 6.28 rad / sec and a temperature of 250 ° C. is in the above range, that is, whether the storage elastic modulus (G ′) is larger than the loss elastic modulus (G ″). It is the same, meaning it is elastic.

  In the present embodiment, as described above, it is considered that a crosslinking reaction between magnesium hydroxide and the cellulose resin occurs, and it is considered that the loss tangent (Tan δ) is controlled within the above range depending on the degree of the crosslinked structure. As a result, fluidity in a high temperature environment is suppressed and excellent flame retardancy is achieved.

  Here, the loss tangent (tan δ) of the resin composition and the resin molded product is the RDA2RHIOS system Ver. It is measured under the conditions of a frequency of 6.28 rad / sec and a temperature of 250 ° C. using 4.3.2 (manufactured by Rheometrics Scientific F.E.).

  Next, each component will be described.

-Cellulose resin-
Cellulose resin refers to a natural polymer compound in which a large number of β-glucose molecules are linearly polymerized by glycosidic bonds, and is a polymer compound that exhibits properties different from glucose, which is a structural unit. It is a kind of so-called beta glucan and has a repeating unit represented by the following structural formula (1).

Cellulose may be modified, and as shown in the following structural formula (2), R ¹ , R ² and R ³ may be hydrogenated or esterified (that is, C _n H _m O a linear, branched, or cyclic acid represented by _x ) and etherified (a linear, branched, or cyclic hydrocarbon represented by C _n H _m ). R ¹ , R ² and R ³ may have different structures, for example, R ¹ may be H, R ² may be methyl, and R ³ may be acetyl.

  The cellulose may be a copolymer having both the repeating unit represented by the structural formula (1) and the repeating unit represented by the structural formula (2).

The cellulose resin in the present embodiment refers to cellulose derived from a natural material, or a resin having a cellulose skeleton obtained by introducing a functional group biologically or chemically using the cellulose as a raw material.
The raw cotton is not only natural cellulose such as cotton linter and wood pulp (broadwood pulp, conifer pulp), but also cellulose having a low degree of polymerization (degree of polymerization 100 to 300) obtained by acid hydrolysis of wood pulp such as microcrystalline cellulose. Used and may be used in combination. The detailed description of cellulose used as these raw materials is, for example, “Plastic Materials Course (17) Fibrous Resin” (by Marusawa, Uda, Nikkan Kogyo Shimbun, published in 1970) and JIII Journal of Technical Disclosure 2001- 1745 (pages 7 to 8) and “Encyclopedia of Cellulose (page 523)” (edited by Cellulose Society, Asakura Shoten, published in 2000) are used, and are not particularly limited.

Examples of the alkyl group represented by R ^{1 to} R ³ in the structural formula (2) include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-octyl group. Group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group Group, n-nonadecyl group, vinyl group, allyl group, 2-butenyl group, 3-pentenyl group, tert-butyl group, 2-methylbutyl group, isovaler group, 2-ethylbutyl group, 2,2-dimethylbutyl group, 2 -Methyl barrel group, 3-methyl barrel group, 4-methyl barrel group, 2-propylpentyl group, 2-methylhexyl group, 2-ethylhexyl group, 2-methyl -2-pentyl, 2,2-dimethylpentyl group, a 2-Okuchiiru group. These groups may be further substituted. Moreover, when there are two or more substituents, they may be the same or different. Preferably, methyl group, ethyl group, propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group A group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, and n-nonadecyl group.

Further, it may be an aliphatic acyl group containing a branched structure, and specific examples thereof include 2-methylbutanoyl group, isovaleryl group, 2-ethylbutanoyl group, t-butylacetyl group, 2-methylvaleryl group, 3-methylvaleryl group. 4-methylvaleryl group, 2-propylpentanoyl group, 2-methylhexanoyl group, 2-ethylhexanoyl group, isostearoyl group, tiglinoyl group, 3,3-dimethylacrylic group, 2-methyl-2-pentenoyl group And citronellyl group.
Among these, t-butylacetyl group, 2-methylvaleryl group, 3-methylvaleryl group, 4-methylvaleryl group, 2-propylpentanoyl group, 2-methylhexanoyl group, 2-ethylbutanoyl group, 2-ethyl are preferable. Examples include hexanoyl group, isostearoyl group, tiglinoyl group, 3,3-dimethylacryl group, 2-methyl-2-pentenoyl group, citronellyl group and the like.
More preferably, t-butylacetyl group, 2-methylvaleryl group, 3-methylvaleryl group, 4-methylvaleryl group, 2-propylpentanoyl group, 2-methylhexanoyl group, 2-ethylbutanoyl group, 2-ethylhexayl group A noyl group, an isostearoyl group, and a citronellyl group.

Although it does not specifically limit as a weight average molecular weight of a cellulose resin, 100,000 or more and 1.5 million or less are preferable, Furthermore, 150,000 or more and 1 million or less are more preferable.
The weight average molecular weight is first measured by size exclusion chromatography (GPC) using a cellulose resin dissolved in a solvent.

-Other resin In the resin composition in the present embodiment, another resin may be further used in combination with the cellulose resin. However, the ratio of the cellulose resin (the content of the cellulose resin / the total content of the cellulose resin and the other resin) when other resins are used in combination is preferably 10% by mass or more, and more preferably 40% by mass. More preferably.

  Examples of the other resins include conventionally known thermoplastic resins, and specifically, polycarbonate resins; polypropylene resins; polyester resins; polyolefin resins; polyester carbonate resins; polyphenylene ether resins; Polyethersulfone resin; Polyarylene resin; Polyetherimide resin; Polyacetal resin; Polyvinyl acetal resin; Polyketone resin; Polyetherketone resin; Polyetheretherketone resin; Polyarylketone resin; Benzimidazole resin; polyparabanic acid resin; selected from the group consisting of aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters, and vinyl cyanide compounds A vinyl polymer or copolymer resin obtained by polymerizing or copolymerizing at least one vinyl monomer; a diene-aromatic alkenyl compound copolymer resin; a vinyl cyanide-diene-aromatic alkenyl compound. Copolymer resin; aromatic alkenyl compound-diene-vinyl cyanide-N-phenylmaleimide copolymer resin; vinyl cyanide- (ethylene-diene-propylene (EPDM))-aromatic alkenyl compound copolymer resin; polyolefin Vinyl chloride resin; chlorinated vinyl chloride resin; and the like. These resins may be used alone or in combination of two or more.

-Flame retardant-
The resin composition according to the present embodiment uses at least magnesium hydroxide and a liquid flame retardant in combination as a flame retardant.

-Liquid flame retardant Liquid flame retardant refers to a flame retardant that is liquid at room temperature (20 ° C).

Although it does not specifically limit as a liquid flame retardant used for this embodiment, A liquid phosphate ester is preferable.
The phosphate ester is a compound having a chemical structure represented by the following general formula.
General formula: (RO) ₃ PO
[Wherein, R represents an aliphatic group or an aromatic ring, the aliphatic group may have a substituent such as an OH group, and the aromatic ring may have a substituent such as an OH group or an alkyl group. ]

Specific examples of the phosphate ester include aliphatic phosphate esters (for example, trimethyl phosphate, triethyl phosphate, etc.), aromatic phosphate esters (for example, triphenyl phosphate, etc.), aromatic condensed phosphate esters, and the like. It is done.
Among these, aromatic condensed phosphate esters are particularly preferably used.

  Examples of the aromatic condensed phosphate ester include pentaerythritol diphosphate and phosphate ester compounds represented by the following general formulas (I) and (II).

In formula (I), Q ¹ , Q ² , Q ³ and Q ⁴ each independently represents an alkyl group having 1 to 6 carbon atoms, Q ⁵ and Q ⁶ each independently represent a methyl group, and Q ⁷ and Q ⁸ each independently represent a hydrogen atom or a methyl group, m1, m2, m3 and m4 each independently represent an integer of 0 or more and 3 or less, and m5 and m6 each independently represent 0 or more and 2 or less. N1 represents an integer of 0 or more and 10 or less.

In formula (II), Q ⁹ , Q ¹⁰ , Q ¹¹ and Q ¹² each independently represents an alkyl group having 1 to 6 carbon atoms, Q ¹³ represents a methyl group, m7, m8, m9 and m10 Each independently represents an integer from 0 to 3, m11 represents an integer from 0 to 4, and n2 represents an integer from 0 to 10.

  In the present embodiment, for example, aromatic condensed phosphate esters such as bisphenol A type, biphenylene type, and isophthal type are preferably used. Commercially available products such as PX-201, PX-202, CR-733S, CR-741, and CR747 manufactured by Daihachi Chemical may be used as the aromatic condensed phosphate ester.

As content of a liquid flame retardant, it is preferable that it is 1 to 30 mass% with respect to the said cellulose resin, Furthermore, 5 to 25 mass% is more preferable, 10 to 20 mass% is more preferable. The following is more preferable.
When the content of the liquid flame retardant with respect to the cellulose resin is not less than the above lower limit value, the surface impact resistance is improved.
On the other hand, when the amount is not more than the above upper limit, advantages such as improved heat resistance of the molded body and less likelihood of bleeding are obtained.

Magnesium hydroxide Magnesium hydroxide used in the present embodiment is a solid flame retardant.

As content of magnesium hydroxide, it is preferable that they are 5 mass% or more and 50 mass% or less with respect to the said cellulose resin, Furthermore, 10 mass% or more and 45 mass% or less are more preferable, 15 mass% or more and 40 mass% or less. The following is more preferable.
When the content of magnesium hydroxide with respect to the cellulose resin is not less than the above lower limit value, the dehydration reaction proceeds and the crosslinking reaction proceeds as the temperature increases, so that flame retardancy is improved.
On the other hand, when it is not more than the above upper limit value, the fluidity becomes appropriate at the time of molding, and a good molded product can be obtained.

Moreover, as a ratio (content of a liquid flame retardant / content of magnesium hydroxide x 100 (mass%)) between magnesium hydroxide and a liquid flame retardant in the resin composition according to the present embodiment, 2 mass% or more and 600 It is preferable that it is mass% or less, Furthermore, 10 mass% or more and 250 mass% or less are more preferable, and 25 mass% or more and 130 mass% or less are still more preferable.
When the ratio between magnesium hydroxide and the liquid flame retardant is equal to or greater than the lower limit, surface impact resistance and flame retardancy are improved.
On the other hand, when the amount is not more than the above upper limit, advantages such as improved heat resistance of the molded body and less likelihood of bleeding are obtained.

-Other flame retardant Moreover, in the resin composition which concerns on this embodiment, you may further add another flame retardant in the range which does not impair the effect.
Examples of other flame retardants include phosphorus, silicone, nitrogen-containing, sulfuric acid, and inorganic hydroxide flame retardants.
Examples of the phosphorus-based flame retardant include condensed phosphate ester, melamine phosphate, ammonium phosphate, and aluminum phosphate. Examples of the silicone-based flame retardant include dimethylsiloxane, nanosilica, and silicone-modified polycarbonate. Examples of the flame retardant include melamine compounds and triazine compounds, examples of the sulfuric acid-based flame retardant include melamine sulfate and guanidine sulfate, and examples of the inorganic hydroxide-based flame retardant include aluminum hydroxide.

-Other ingredients-
-Plasticizer In this embodiment, you may add a plasticizer with respect to a cellulose resin from a viewpoint of improving the moldability of a resin molding further.
Examples of the plasticizer include triethyl citrate, acetyl triethyl citrate, dibutyl phthalate, diaryl phthalate, diethyl phthalate, dimethyl phthalate, triethyl phosphate, triphenyl phosphate, tripropionine, dibutyl tartrate, triacetin, triacetin Examples thereof include phenyl phosphate, tricresyl phosphate, mixed group dibasic acid ester and the like.

  Among the plasticizers mentioned above, triethyl citrate, acetyl / triethyl citrate, triphenyl phosphate, triacetin, and mixed dibasic acid esters are more preferably used.

  As content of a plasticizer, it is preferable that they are 5 mass% or more and 40 mass% or less with respect to the said cellulose resin, Furthermore, 10 mass% or more and 30 mass% or less are more preferable.

Other components The resin composition according to the present embodiment may further include other components than those described above as necessary.
Other components include, for example, compatibilizers, antioxidants, mold release agents, light proofing agents, weathering agents, colorants, pigments, modifiers, anti-drip agents, antistatic agents, anti-hydrolysis agents, and filling. Agents, reinforcing agents (glass fiber, carbon fiber, talc, clay, mica, glass flake, milled glass, glass beads, crystalline silica, alumina, silicon nitride, alumina nitride, boron nitride, etc.).
The content of these components is preferably 0% by mass or more and 5% by mass or less with respect to the entire resin composition. Here, “0 mass%” means that other components are not included.

[Method for Producing Resin Composition]
The resin composition according to this embodiment is produced, for example, by melt-kneading a mixture of the above components. In addition, the resin composition according to the present embodiment is produced, for example, by dissolving the above components in a solvent. Examples of the melt-kneading means include known means, and specific examples include a twin screw extruder, a Henschel mixer, a Banbury mixer, a single screw extruder, a multi-screw extruder, and a kneader.

<Resin molding>
The resin molding which concerns on this embodiment consists of the resin composition which concerns on this embodiment. That is, the resin molded body according to the present embodiment is configured with the same composition as the resin composition according to the present embodiment.
Specifically, the resin molded body according to the present embodiment is obtained by molding the resin composition according to the present embodiment. As the molding method, for example, injection molding, extrusion molding, blow molding, hot press molding, calendar molding, coating molding, cast molding, dipping molding, vacuum molding, transfer molding, or the like may be applied.

  The molding method of the resin molded body according to the present embodiment is preferably injection molding because it has a high degree of freedom in shape. The resin composition according to the present embodiment has high fluidity and can be applied by injection molding. The injection molding may be performed using a commercially available apparatus such as NEX150 manufactured by NISSEI RESIN INDUSTRY, NEX70000 manufactured by NISSEI RESIN INDUSTRY, SE50D manufactured by Toshiba Machine.

  The molding temperature at the time of molding the resin molded body (for example, cylinder temperature in the case of injection molding) is preferably 230 ° C. or higher and 260 ° C. or lower, more preferably 230 ° C. or higher and 250 ° C. or lower. The mold temperature in the case of injection molding is, for example, 40 ° C. or more and 80 ° C. or less, and more preferably 45 ° C. or more and 70 ° C. or less.

  The resin molded body according to the present embodiment is suitably used for applications such as electronic / electrical equipment, office equipment, home appliances, automobile interior materials, and containers. More specifically, casings for electronic / electrical equipment and home appliances; various parts of electronic / electrical equipment and home appliances; interior parts for automobiles; storage cases such as CD-ROM and DVD; tableware; beverage bottles; Wrap material; film; sheet;

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[Examples 1 and 2, Comparative Examples 1 to 7]
The compounding components shown in Tables 1 to 3 below were melt-mixed at 230 ° C. using a twin screw extruder to prepare a resin composition.

  Each of these resin compositions was charged into an injection molding machine (NEX500 manufactured by Nissei Plastic Industry), and a resin molded body was formed at a cylinder temperature of 230 ° C. and a mold temperature of 60 ° C.

In addition, the detail of each compounding component described in the following Tables 1 to 3 is as follows.
Cellulose resin “DAC L-50” = manufactured by Daicel Corporation, trade name: L-50
Plasticizer “DF” = mixed dibasic acid ester, manufactured by Daihachi Chemical Co., Ltd., trade name: DAIFACTY-101
-Solid flame retardant "KISUMA" = Magnesium hydroxide, manufactured by Kyowa Chemical Industry Co., Ltd., trade name: KISUMA-5A
“MGZ” = magnesium hydroxide, manufactured by Sakai Chemical Industry Co., Ltd., trade name: MGZ-3
“Calcium carbonate” = Shiraishi Calcium Co., Ltd., trade name: Whiten SSB Blue “Talc” = Nihon Talc Co., Ltd., trade name: D-1000
-Liquid flame retardant "CR741" = aromatic condensed phosphate ester, manufactured by Daihachi Chemical Industry Co., Ltd., trade name: CR741

<Evaluation test>
・ Flame retardance test Using a corn calorimeter (CCM, manufactured by Toyo Seiki Co., Ltd., product name: MCM), the resin compositions obtained in Examples and Comparative Examples were subjected to a flame retardance test by the following method. , “Maximum heat generation rate, average heat generation rate, total heat generation amount, combustion effective heat generation amount, ignition time, combustion time, residual rate”.
As a specific test method, a test sample having a size of 30 mm × 30 mm and a thickness of 2 mm was molded by a melt press, and the measurement was performed with a radiation amount of 25 W and a distance between the cone and the sample set to 30 mm.

-Thermogravimetric measurement The thermogravimetric analysis using TG-DTA (product name: TG / DTA6200) about the resin composition obtained in the Example and the comparative example "Tg residue rate. , DTG peak top temperature ".
As a specific measuring method, the temperature was raised to 600 ° C. at a temperature rising rate of 20 ° C./min in a nitrogen stream, and the peak top temperature and the residue rate were confirmed.

-Weight average molecular weight measurement by GPC About the resin composition obtained in the Example and the comparative example, "weight average molecular weight Mw" was calculated | required using GPC (chromatograph, the Tosoh Corporation make, product name: HLC8120GPC). In addition, molecular weight measurement was implemented about each of what heated the resin composition at 220 degreeC for 5 minutes, and what performed the below-mentioned viscoelasticity measurement test.
As a specific measurement method, a measurement sample was prepared with a solvent: THF and a concentration of 0.1 w / v%, and a molecular weight was calculated in terms of conversion from a polystyrene standard sample.

-Viscoelasticity measurement About the resin composition obtained in the Example and the comparative example, RDA2RHIOS system Ver. Using 4.3.2 (Rheometrics Scientific F.E. Co., Ltd.), viscoelasticity was measured under the conditions of a frequency of 6.28 rad / sec and temperatures of 220 ° C. and 250 ° C. Modulus (G ′), loss modulus (G ″), viscosity (η *), loss tangent (tan δ) ”.

  The resin composition obtained in Example 1 (magnesium hydroxide 20% by mass, liquid flame retardant 12% by mass) and the resin composition obtained in Comparative Example 4 (magnesium hydroxide 20% by mass) were used. The viscoelasticity measurement results are shown in FIGS. 1 and 2, respectively.

-Surface impact resistance Moreover, the following tests were implemented about the resin molding obtained in the Example and the comparative example, and surface impact resistance was evaluated.
As a specific measurement method, a test piece of 60 mm × 60 mm and a thickness of 2 mm was formed, and using this, a steel ball having a weight of 500 g and a diameter of 50 mm was dropped from a height of 800 mm, and evaluated according to the following evaluation criteria. .
(Evaluation criteria)
A: No change B: Cracks C: Break

-Moldability Moreover, the following tests were implemented about the resin composition obtained by the Example and the comparative example, and the moldability was evaluated.
As a specific measurement method, an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., NEX500) is used with a bar flow mold (thickness 2 mm, width 10 mm), cylinder temperature 230 ° C., mold temperature 60 ° C., injection pressure 100 MPa. A molded body was formed by
(Evaluation criteria)
A: Resin filled to the tip and constant thickness B: Resin filled to the tip but thin at the tip C: Resin not filled to the tip

Claims (7)

  A resin composition comprising a cellulose resin, magnesium hydroxide, and a liquid flame retardant.   The resin composition according to claim 1, wherein a content of the magnesium hydroxide is 5% by mass or more and 50% by mass or less with respect to the cellulose resin.   The resin composition according to claim 1 or 2, wherein a content of the liquid flame retardant is 1% by mass or more and 30% by mass or less with respect to the cellulose resin.   A resin molded body containing a cellulose resin, magnesium hydroxide, and a liquid flame retardant.   The resin molded body according to claim 4, wherein the content of the magnesium hydroxide is 5% by mass or more and 50% by mass or less with respect to the cellulose resin.   The resin molded body according to claim 4 or 5, wherein a content of the liquid flame retardant is 1% by mass or more and 30% by mass or less with respect to the cellulose resin.   The resin molded product according to any one of claims 4 to 6, wherein the resin composition according to any one of claims 1 to 3 is molded at a temperature of 230 ° C or higher and 260 ° C or lower. .