JP3356824B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition containing a hot-melt polyurethane foam, and more particularly to a polyurethane foam and a thermoplastic resin composition which can be easily reused. INDUSTRIAL APPLICABILITY The present invention is used not only as a cushion, pillow, toy such as a plush toy, a doll, a molded article, but also as a shock absorbing material for a pad, a mat, etc., as well as packaging, packaging materials (especially reused products) for equipment, food, and other broken items. Widely used for.

[0002]

2. Description of the Related Art Conventional flexible polyurethane foams have been widely used for composite products which are composited with a thermoplastic resin. When this composite product is heated and melted as it is, pelletized, or when re-molded using a thermoplastic resin molding machine according to a conventional method, both are not mixed uniformly,
Since polyurethane particles float on the surface of the thermoplastic resin and separate from each other, these polyblends cannot be obtained,
Therefore, reuse and reshaping were extremely difficult. Therefore, when it is desired to separate them, it is customary to physically or chemically separate them and use them for each purpose. That is, since a composite product such as a co-molded product of polyurethane foam and another polyurethane foam, a laminated product of PVC and polyurethane foam cannot be heated and melted or extruded and re-molded as it is, the foam and the thermoplastic resin are mixed together. There is also known a method of physically stripping and pulverizing the stripped foam to reshape the foam, or decomposing the foam with glycol or the like to liquefy and recover it as a polyol (JP-B-46-200).
No. 69, Japanese Patent Publication No. 53-34000).

[0003]

However, in this method, the process is complicated, the recovery efficiency is not excellent, and it is difficult to apply it economically. On the other hand, the thermoplastic resin is regenerated and formed into pellets. However, since the regenerated pellets inevitably cause the urethane solid to float on the surface and remain, high-quality products cannot be regenerated. Furthermore, in order to make the above-mentioned conventional polyurethane foam compatible with a thermoplastic resin,
Although heated near the melting temperature of the thermoplastic resin, this polyurethane foam does not melt, so that it was not possible to obtain an interdispersed polymer blend even if the density and physical properties were adjusted. Also, although a method for producing an allohanate polyisocyanate is known in Japanese Patent Application Laid-Open No. 46-1671, the use of this method to produce a hot-melt polyurethane foam that melts at high temperatures and has excellent reusability is described. Not suggested at all.

The present invention overcomes the above-mentioned drawbacks, and provides a high-quality polymer blend in which a heat-fusible polyurethane foam which can be easily and efficiently recovered and reused is uniformly dispersed in a thermoplastic resin. An object of the present invention is to provide a resin composition that can be provided and has excellent reusability.

[0005]

Means for Solving the Problems The present inventors have made intensive studies on recyclable polyurethane foams and polymer blends using the same, and have completed the present invention. That is, the thermoplastic resin of the first invention
The composition is manufactured by foaming using a urethane raw material containing an allohanate isocyanate and a polyol having a structure having an allohanate bond and having an allohanate conversion of 40 to 70% by weight, and having a heat melting temperature of 1%.
Heat-meltable polyurethane foam with a temperature of 90 ° C or higher
Hot melt of the heat-fusible polyurethane foam
It is characterized by being heated to a melting temperature or higher and kneaded .

[0006] The above "arohanate isocyanate" has a structure in which one mole of isocyanate is added to urethane as shown in the following formula. RNHCO ₂ R '+ RNCO (or 2RNCO + R'O
H) = RNHCO-N (R) CO ₂ R ′ In the present invention, the conversion of the allohanate is from 40 to 70.
% By weight, and includes bonds of urethane, urea, burette, etc. in addition to the above-mentioned allohanate bonds. The conversion rate of this allohanate is a value (unit: wt%) obtained by GPC (gel permeation chromatography) measurement.
Which is obtained by the following equation. Conversion rate (% by weight) = [Arohanate isocyanate amount (parts by weight) / total isocyanate amount (parts by weight)] × 100 When the conversion of the polyisocyanate exceeds 70% by weight, the viscosity of the isocyanate increases, so that the foam When the content is less than 40% by weight, the concentration of the allohanate group contained becomes small, and the heat melting property at high temperatures is lost, which is not preferable. The conversion is particularly preferably in the range of 45 to 60% by weight. that is,
This is because they are easily melted by heating or kneading, and exhibit thermoplastic (melting) properties to be completely compatible with the thermoplastic resin.

The types of (poly) isocyanate used include aromatic TDI, MDI, and polymeric MD.
I, NDI, PPDI, XDI, TMXDI or aliphatic HDI, H12MDI, IPDI, LDI, IP
C, hydrogenated XDI, CHDI, TODI, and modified products thereof can be used. Of these, TDI, MD
The use of I, IPDI and their variants is suitable.
Also, the conversion of polyisocyanates to allohanates is
The target product can be obtained by variously selecting the raw material composition, heating conditions, pressurizing conditions, and the like. For example, the heating temperature is preferably 20 ° C. or higher, particularly preferably 70 to 100 ° C.

As the polyurethane foam to be produced,
Any type may be used as long as it shows heat melting property, and the type and form are not particularly limited. Its density is usually between 0.005 and 1.000.

As the above-mentioned "polyol", known polyols such as polyether polyol and polyester polyol can be used. The polyether polyol is preferably a bifunctional or trifunctional polyol having a molecular weight of 1,000 to 10,000 and similarly, a polyester polyol is preferably a bifunctional or trifunctional polyol having a molecular weight of 1,000 to 5,000.
Functional ones are preferred.

[0010] Further, as other compounding raw materials for producing a polyurethane foam, known polyurethane plasticizers (for example, DOP, DBP, TOP, etc.), foaming agents (water,
HCFC, air, nitrogen, pentane, methylene chloride, nitroalkane, formic acid, etc., and flame retardants (phosphorous halides such as TCPP, etc.) can be used. Further, dispersants, cell open agents (polyether siloxane, Known materials such as sulfonated sodium ricinoleate) can be used.
The NCO / OH equivalent ratio (so-called isocyanate index) is preferably 70 or more, particularly preferably 80 or more.

[0011] The thermoplastic resin composition of the first invention is characterized in that the above-mentioned heat-fusible polyurethane foam and the thermoplastic resin are kneaded by heating to a temperature not lower than the heat-melting temperature of the heat-fusible polyurethane foam. And Examples of the above-mentioned “thermoplastic resin” include acrylonitrile butadiene styrene resin (referred to as ABS), polystyrene (referred to as PS), polyvinyl chloride, polyoxymethylene, polyester, polyamide resin, ethylene-vinyl acetate copolymer, and modifications thereof. A thermoplastic resin or the like can be used. The thermoplastic resin composition blended by melting the polyurethane can retain the thermoplastic properties as it is.

The amount of the hot-melt polyurethane foam is 0.005 parts by weight based on 100 parts by weight of the thermoplastic resin.
-10 parts by weight. With this amount, the hot-melt polyurethane foam is AB
Even when kneaded with a thermoplastic resin such as S or PS, the physical properties of the resin composition are hardly affected and the impact resistance can be improved. In particular, in order to obtain a material having almost the same physical properties as the thermoplastic resin used, 0.00
About 5 to about 10 (particularly about 0.005 to about 6 ) can be used. It can also be observed under an electron microscope that a uniform dispersion blend of the polymer was obtained in the state of sea and island of the polymer.

Further, the mixing of the thermoplastic resin and the polyurethane foam can be carried out by heating or under pressure, and for example, all known methods such as kneading by a kneader and extrusion kneading can be adopted. Alternatively, these mixtures may be pelletized and remolded, or these resins may be directly kneaded and molded by regeneration.

Further, as shown in the second invention, a urethane raw material containing an allohanate isocyanate and a polyol having a structure having an allohanate bond and having an allohanate conversion of 40 to 70% by weight, and a thermoplastic resin (filled) And then kneading by heating to above the hot melt temperature of the hot melt polyurethane foam produced from the urethane raw material and kneading. Can be. In this case, after the use as a foam, a predetermined composition can be produced at a time without adding or using another resin, which is very useful.

[0015]

The present invention will be described below in detail with reference to examples. (1) Preparation of Allohanate Polyisocyanate No. 2 was prepared using 2,4-TDI. Five types of allohanate isocyanates 1 to 5 were synthesized under the following conditions, and the results are shown in Table 1. In the table, NCO%,
The viscosity and the conversion of alohanate are also shown. In addition, this allohanate conversion rate is a value (unit;
% By weight) and was determined by the following equation. Conversion (% by weight) = [Arohanate isocyanate amount (parts by weight) / total isocyanate amount (parts by weight)] × 100 The GPC measurement was performed as follows. That is, about 10 mg of the prepared allohanate isocyanate
Was precisely weighed and dissolved in 10 ml of THF (tetrahydrofuran) to adjust the concentration to 0.1% (wt / vol). The composition of this solution was examined by GPC using THF as an eluent, polystyrene gel as a filler, and a column having a size of 8 mm x 300 mm, and the amount of alohanate isocyanate was determined.

[Synthesis conditions] While maintaining a predetermined amount of diethylene glycol (DEG) at 70 ° C or less, 2,4-tolylene diisocyanate (2,4-TDI) under a nitrogen stream.
Add to Next, zinc acetylacetone, which is an allohanation catalyst, was added to the reaction mixture, and the mixture was reacted for a predetermined time while maintaining the temperature at 70 ° C., thereby obtaining modified isocyanates having different NCO values. According to the results shown in Table 1, as the conversion of allohana in each isocyanate was increased, the viscosity increased in proportion to the conversion. Therefore, as the isocyanate for foam, the conversion rate is 40-6.
0% by weight (NCO%; about 30 to 26%, viscosity: about 0.5
８０80 Pa · s) is suitable.

[0017]

[Table 1]

(2) Manufacture of urethane foam Each foam (comparative products No. 1-2, practical products No. 3-1)
1) is a raw material composition shown in Table 2 (raw material types are shown below).
Was used to produce a foam under the following foaming conditions.

[0019]

[Table 2]

[Raw material type] Polyol 1: "No. 38" (manufactured by Sanyo Chemical): Polyether type trifunctional 2: "N4042" (manufactured by Nippon Polyurethane): Polyester type bifunctional 3: "PL2100" (manufactured by Sanyo Chemical) ): Polyether type bifunctional chain extender 1: Ethylene Glycol 2: “KL-210” (manufactured by Mitsui Toatsu Chemicals) Catalyst 1: “LV33” (manufactured by Chukyo Yushi) 2: “Niax A-1” (manufactured by UCC) 3) “DABCO-XDM” (manufactured by Sankyo Air Products) Foam stabilizer 1: “SF2961” (manufactured by Toray Dow Corning Silicone) 2: “SRX294A” (manufactured by Toray Dow Corning Silicone) 3: “SZ-1946” (Japan) 4: F-122 (Shin-Etsu Silicon) Isocyanate 1: TDI-80 (Nippon Polyure) Emissions, Ltd.) 2: "SBU-0379" (manufactured by SBU) 3: allophanate isocyanate No. 4 (conversion rate: 50.7 % by weight) 4: Allohanate isocyanate No. 4 1 (conversion rate; 63.3 % by weight) 5: Allohanate isocyanate No. 1 5 (conversion rate; 42.0 % by weight)

[Expansion conditions] 100 parts by weight of a polyol is
Calculated calculated amount of alohananate isocyanate, water,
Mix with catalyst and foam stabilizer. The reaction mixture foamed immediately after stirring to give an elastic foam. Table 3 shows the physical properties of the foam produced as described above. According to this result, when the allohanate isocyanate was used (N
o. In 3 to 11), foaming was possible in the same manner as ordinary isocyanates.

[0022]

[Table 3]

(3) Melting Test of Foam A melting test of each foam produced as described above was conducted. In this test method, a foam sliced to a thickness of 1 cm was placed on an aluminum foil in a circulation oven controlled at the test temperature shown in Table 4, and the state of the foam after 10 minutes was visually checked. Table 4 shows the results. In addition, the display of evaluation is x:
No melting, Δ: partial melting, ：: complete melting. According to this result, in Comparative Examples (Nos. 1 and 2) containing no allohanate isocyanate, they did not melt even when heated to 230 ° C. On the other hand, in Examples (Nos. 3 to 11) containing allohanate isocyanate, 190 to 2
When heated to 30 ° C., it becomes molten.

[0024] The ordinary thermoplastic resin generally shows a linear structure, but the polyurethane foam of the present invention shows a hot-melt (plastic) property while having a branched structure. The melting temperature can be adjusted depending on the properties (polyester or polyether, the number of functional groups or the molecular weight, etc.) of the polyol to be used. The foam that melts at the lowest temperature is a foam using a bifunctional polyester polyol (Nos. 3 and 4), followed by a bifunctional polyether polyol (No.
6) The melting temperature changes in the order of trifunctional polyether polyol (No. 5) depending on the polyol used. Furthermore, since the mixed system (mixed system of trifunctional and bifunctional polyether polyols; No. 7) shows an intermediate melting behavior, the melting behavior is adjusted by mixing polyols having different numbers of functional groups. You can also. When the density is reduced, (No. 8,
No. In 9) as well, the melting temperature increased, but the melting behavior was observed for all foams.

[0025]

[Table 4]

(4) Kneading test of polyurethane foam and thermoplastic resin Each of the foams prepared in the above (2) (Nos. 1-3 and 5)
6) and the thermoplastic resin were kneaded by the following method.
After slicing each foam (shown in Tables 5 and 6) into 1 cm squares, and drying in a vacuum oven at 80 ° C. for 2 hours, each foam and a thermoplastic resin (ABS) shown in Table 5 [trade name: “38R” ", Manufactured by Nippon Synthetic Rubber Co., Ltd.] and a thermoplastic resin (PS) shown in Table 6 (trade name:" IT40 ", manufactured by Idemitsu Petrochemical Co., Ltd.) (also vacuum dried). In a conical mixer for 3-5 minutes, 200
Kneaded at ℃. After kneading, the resin is pulverized and then injection molded, and the physical properties (tensile strength, Izod impact value,
(Glass transition temperature and dispersion state). The results are shown in Tables 5 and 6. The tensile strength is JISK7113,
The Izod impact value was measured by JIS K 7110, the glass transition temperature was measured by JIS K 7121, and the dispersion state was measured by SEM observation.

[0027]

[Table 5]

[0028]

[Table 6]

When the foam was kneaded using ABS as a resin (Table 5), the comparative product: the strength was reduced as compared with the ABS alone (original), but the actual product (3 to 10 p.
bw addition), the strength hardly decreased in any case. Further, although the Izod impact value was remarkably reduced in the comparative product, the reduction was remarkably small in the actual product, and the difference between the two was remarkably large. In the case of PS (Table 6), the same tendency was observed, but the impact value was improved as observed in the ordinary polymer blend. In this way, the form of the product is improved from the viewpoint of recycling and the improvement of resin properties by blending [this is superior to PS alone (original)]. ) Also proved to be effective.

It should be noted that the present invention is not limited to the specific embodiments described above, but can be variously modified within the scope of the present invention in accordance with the purpose and application. That is,
The type of isocyanate and polyol to be used, the conversion rate of allohanate, the type of thermoplastic resin and the amount thereof are variously selected.

[0031]

As described above, the polyurethane foam of the present invention has 190
Since it is melted by heating at a temperature of not less than ℃, it can be easily and efficiently recovered and reused. In addition, in the thermoplastic resin composition comprising the heat-fusible polyurethane foam and the thermoplastic resin, since the heat-fusible polyurethane foam is uniformly dispersed in the thermoplastic resin, a high-quality blend resin (polymer blend) is used. It can be provided, and the whole is also thermoplastic, so it is excellent in reusability.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-107620 (JP, A) JP-A-1-245010 (JP, A) JP-A-54-14921 (JP, A) JP-A-48-48 8897 (JP, A) JP-A-46-197 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18/87 C08L 75/04-75/12 C08L 101/00-101/14

Claims (3)

(57) [Claims] 1. A foaming and manufacturing method using a urethane raw material containing an allohanate isocyanate and a polyol having a structure having an allohanate bond and having an allohanate conversion of 40 to 70% by weight, and having a heat melting temperature of 190. Heat-meltable polyurethane foam and heat above ℃
A plastic resin and heat of the hot-melt polyurethane foam.
It is characterized by being heated and kneaded above the melting temperature
Thermoplastic resin composition . 2. It has a structure having an allohanate bond and
This alohanate conversion rate is 40 to 70% by weight.
Urethane containing rohanate isocyanate and polyol
Foamed using a raw material and a thermoplastic resin, and then
A thermoplastic resin composition obtained by heating and kneading the hot-melt polyurethane foam produced from the urethane raw material to a temperature equal to or higher than the hot-melt temperature. 3. The arrangement of said hot-melt polyurethane foam.
The total amount is 0.1 to 100 parts by weight of the thermoplastic resin.
3. The thermoplastic resin composition according to claim 1, wherein the amount is from 005 to 10 parts by weight .