FILLER COMPOSITION AND POLYOLEFIN RESIN COMPOSITION

Abstract

A filler composition comprising fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m in a ratio by weight in the range of 100:0.001 to 100:50, and a polyolefin resin composition comprising a polyolefin resin, fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m, in which the polyolefin resin and fibrous basic magnesium sulfate particles are present in a weight ratio of 99:1 to 50:50, and the non-fibrous inorganic micro-particles are present in an amount of 0.001 to 50 weight parts per 100 weight parts of the basic fibrous magnesium sulfate particles and/or in an amount of 0.0002 to 10 weight parts, per 100 weight parts of the resin.

Claims

1. A filler composition comprising fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m in a ratio by weight in the range of 100:0.001 to 100:50.

2. The filler composition of claim 1, wherein the non-fibrous inorganic micro-particles are spherical silicon dioxide particles.

3. The filler composition of claim 2, wherein the spherical silicon dioxide particles have an average particle diameter in the range of 0.005 to 0.1 m.

4. The filler composition of claim 1, wherein the fibrous basic magnesium sulfate particles have an average longer diameter in the range of 5 to 50 m and an average shorter diameter in the range of 0.1 to 2.0 m, and an aspect ratio in terms of the average longer diameter/average shorter diameter is in the range of 5 to 50.

5. The filler composition of claim 1, wherein the average diameter of the non-fibrous inorganic micro-particles is in the range of to 1/500 per an average shorter diameter of the fibrous basic magnesium sulfate particles.

6. The filler composition of claim 1, wherein the non-fibrous inorganic micro-particles are contained in an amount of 0.001 to 8 weight parts, per 100 weight parts of the fibrous basic magnesium sulfate particles.

7. The filler composition of claim 1, wherein the non-fibrous inorganic micro-particles are contained in an amount of 0.005 to 2 weight parts, per 100 weight parts of the fibrous basic magnesium sulfate particles.

8. The filler composition of claim 1, wherein the filler composition has a surface treated with a coupling agent.

9. A polyolefin resin composition comprising a polyolefin resin, fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m in which the polyolefin resin and fibrous basic magnesium sulfate particles are contained in a ratio by weight in the range of 99:1 to 50:50, and the non-fibrous inorganic micro-particles are contained in an amount of 0.001 to 50 weight parts per 100 weight parts of the fibrous basic magnesium sulfate particles and/or in an amount of 0.0002 to 10 weight parts per 100 weight parts of the resin.

10. The polyolefin resin composition of claim 9, wherein the non-fibrous inorganic micro-particles are spherical silicon dioxide particles.

11. The polyolefin resin composition of claim 9, wherein the fibrous basic magnesium sulfate particles have an average longer diameter in the range of 5 to 50 m and an average shorter diameter in the range of 0.1 to 2.0 m, and an aspect ratio in terms of the average longer diameter/average shorter diameter is in the range of 5 to 50.

12. The polyolefin resin composition of claim 9, wherein the average diameter of the non-fibrous inorganic micro-particles is in the range of to 1/500 per an average shorter diameter of the fibrous basic magnesium sulfate particles.

13. The polyolefin resin composition of claim 9, wherein the non-fibrous inorganic micro-particles are contained in an amount of 0.005 to 2 weight parts, per 100 weight parts of the fibrous basic magnesium sulfate particles.

14. The polyolefin resin composition of claim 9, wherein the non-fibrous inorganic micro-particles have surfaces treated with a coupling agent.

15. The polyolefin resin composition of claim 9, wherein the polyolefin resin is a polypropylene resin.

Description

EXAMPLES

Comparison Example 1

[0044] 85 Weight parts of polypropylene resin [MFR (temperature 230 C., load 2.16 kg): 52 g/min.) and 15 weight parts of fibrous basic magnesium sulfate particles (MOS A-1, available from Ube Material Industries, Limited, average longer diameter: 15 m, average shorter diameter: 0.5 m) were mixed. The resulting mixture was melt-kneaded and extruded at a temperature of 230 C., rotation of screws: 250 r.p.m.) by means of a double screw melt-kneading extruder (Laboplast Mill Micro, L/D=18, available from Toyo Seiki Seisakusho Co., Ltd.) to give a melt-kneaded product in the form of a strand. The strand was cut to give pellets of a polypropylene resin composition containing the fibrous basic magnesium sulfate particles.

[0045] The resulting pellets of polypropylene resin composition was introduced into a small-sized injection molding machine (TE 3-1E, available from Nissei Jushi Industries, Ltd.) to produce specimens in the form of a small dumbbell (Type 1BB described in JIS-K-7162).

[0046] The specimens were subjected to measurements of Izod impact strength and flexural modulus. The Izod impact strength was 3.7 kJ/m.sup.2 and the flexural modulus was 3.5 GPa.

[0047] The Izod impact strength was measured according to JIS-K-7110, by means of Notching machine (available from Imoto Seisakusho Co., Ltd.).

[0048] The flexural modulus was measured by means of a universal dynamic tester (Strograph VGF, available from Toyo Seiki Seisakusho Co., Ltd.).

Example 1

[0049] 100 Weight parts of the fibrous basic magnesium sulfate particles employed in Comparison Example 1 were mixed with 0.15 weight part of spherical silica particles (Adomanano, available from Adomatex Co., Ltd., average particle diameter: 10 nm, determined from SEM image), by means of a dry mixer, to produce a filler composition.

[0050] The procedures of Comparison Example 1 were repeated except that 15 weight parts of the resulting filler composition were incorporated into 85 weight parts of the polypropylene resin, to produce pellets of polypropylene resin composition. The pellets were then subjected to the measurements of Izod impact strength and flexural modulus. It was confirmed that the resulting flexural modulus was essentially the same as that measured in Comparison Example 1. However, the Izod impact strength was apparently higher than that measured in Comparison Example 1.

Comparison Example 2

[0051] 85 Weight parts of polypropylene resin [MFR (temperature 230 C., load 2.16 kg): 52 g/min.) and 15 weight parts of fibrous basic magnesium sulfate particles employed in Comparison Example 1 were mixed.

[0052] The resulting mixture was melt-kneaded and extruded at a temperature of 230 C., rotation of screws: 90 r.p.m.) by means of a double screw melt-kneading extruder (L/D=25, available from Imoto Seisakusho Co., Ltd.), to give a melt-kneaded product in the form of a strand. The strand was cut to give pellets of a polypropylene resin composition containing the fibrous basic magnesium sulfate particles.

[0053] The resulting pellets of polypropylene resin composition was introduced into a small-sized injection molding machine (manually operable injection molding machine, Handy Try, available from Shinko Cellbit) and injected at cylinder temperature of 230 C. and mold temperature of 50 C., to produce specimens in the form of strip (width 5 mm, thickness 2 mm, length 50 mm).

[0054] The specimens were subjected to measurements of Izod impact strength and flexural modulus. The results of the measurements are set forth in Table 1.

[0055] The Izod impact strength was measured by means of an Izod impact tester (available from Maise Tester Co., Ltd.) according to the measuring method described in JIS-K-7110.

[0056] The flexural modulus was measured by means of an electric measuring stand (MX-500N, available from Imada Co., Ltd.) and a digital force gauge (ZTA-500N, available from Imada Co., Ltd.) under the conditions of a load rate of 10 mm/min. and a distance between the support points of 40 mm.

Example 2

[0057] 100 Weight parts of the fibrous basic magnesium sulfate particles were mixed with 0.015 weight part of spherical silica particles (both employed in Comparison Example 1) by means of a dry mixer, to produce a filler composition.

[0058] The procedures of Comparison Example 2 were repeated except that 15 weight parts of the resulting filler composition were incorporated into 85 weight parts of the polypropylene resin, to produce pellets. The pellets were then converted into specimens in the manner described in Comparison Example 2 and subjected to the measurements of Izod impact strength and flexural modulus. The results of the measurements are set forth in Table 1.

Example 3

[0059] The procedures of Example 2 were repeated except that the spherical silica particles were mixed in an amount of 0.15 weight part, to produce a filler composition.

[0060] The filler composition was incorporated into the polypropylene resin in the same manner to produce pellets. The pellets were then converted into specimens in the same manner and subjected to the measurements of Izod impact strength and flexural modulus. The results of the measurements are set forth in Table 1.

Example 4

[0061] The procedures of Example 2 were repeated except that the spherical silica particles were mixed in an amount of 1.5 weight parts, to produce a filler composition.

[0062] The filler composition was incorporated into the polypropylene resin in the same manner to produce pellets. The pellets were then converted into specimens in the same manner and subjected to the measurements of Izod impact strength and flexural modulus. The results of the measurements are set forth in Table 1.

TABLE-US-00001 TABLE 1 Izod impact flexural modulus C/B strength (kJ/m.sup.2) (GPa) Com. Ex. 2 0 2.1 2.8 Example 2 0.00015 2.4 3.0 Example 3 0.0015 2.7 3.1 Example 4 0.015 3.0 3.1 Remark: C/B means a ratio of the amount by weight of spherical silica particles (C) per 100 weight parts of the fibrous basic magnesium sulfate particles (B).

Example 5

[0063] 85 Weight parts of polypropylene resin [MFR (temperature 230 C., load 2.16 kg): 52 g/min.), 15 weight parts of fibrous basic magnesium sulfate particles (MOS A-1, available from Ube Material Industries, Limited, average longer diameter: 15 m, average shorter diameter: 0.5 m) and 0.0015 weight part of spherical silica particles (Adomanano, available from Adomatex Co., Ltd., average particle diameter: 10 nm, determined from SEM image, by means of a dry mixer. The resulting mixture was melt-kneaded and extruded at a temperature of 230 C., rotation of screws: 250 r.p.m.) by means of a double screw melt-kneading extruder (Laboplast Mill Micro, L/D=18, available from Toyo Seiki Seisakusho Co., Ltd.) to give a melt-kneaded product in the form of a strand. The strand was cut to give pellets of the polypropylene resin composition containing the fibrous basic magnesium sulfate particles and spherical silica particles.

Example 6

[0064] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 0.015 weight part, to give pellets of the polypropylene resin composition.

Example 7

[0065] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 0.15 weight part, to give pellets of the polypropylene resin composition.

Example 8

[0066] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 0.75 weight part, to give pellets of the polypropylene resin composition.

Example 9

[0067] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 1.0 weight part, to give pellets of the polypropylene resin composition.

Example 10

[0068] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 1.5 weight parts, to give pellets of the polypropylene resin composition.

Example 11

[0069] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 4.5 weight parts, to give pellets of the polypropylene resin composition.

Example 12

[0070] The procedures of Example 5 were repeated except for using the spherical silica particles in an amount of 7.5 weight parts, to give pellets of the polypropylene resin composition.

Comparison Example 3

[0071] The procedures of Example 5 were repeated except for using no spherical silica particles, to give pellets of the polypropylene resin composition.

[0072] The amounts in terms of weight part(s) of the polypropylene resin, fibrous basic magnesium sulfate particles and spherical silica particles, the ratio of the spherical silica particles per 100 weight parts of the polypropylene resin, and the ratio of the spherical silica particles per 100 weight parts of the fibrous basic magnesium sulfate particles employed in Examples 5 to 12 and Comparison Example 3 are set forth in Table 2 below.

TABLE-US-00002 TABLE 2 A B C C/A C/B Example 5 85 15 0.0015 0.0018 0.010 Example 6 85 15 0.015 0.018 0.10 Example 7 85 15 0.15 0.18 1.0 Example 8 85 15 0.75 0.88 5.0 Example 9 85 15 1.0 1.2 6.7 Example 10 85 15 1.5 1.8 10 Example 11 85 15 4.5 5.3 30 Example 12 85 15 7.5 8.8 50 Com. Ex. 3 85 15 0 0 0 Remarks: A: Amount of polypropylene resin (weight parts) B: Amount of fibrous basic magnesium sulfate particles (weight parts) C: Amount of spherical silica particles (weight part(s)) C/A: Amount (weight part(s)) of spherical silica particles per 100 weight parts of polypropylene resin C/B: Amount (weight part(s)) of spherical silica particles per 100 weight parts of fibrous basic magnesium sulfate particles

[Evaluations]

[0073] The pellets of polypropylene resin compositions produced in Examples 5 to 12 and Comparison Example 3 were converted into specimens in the form of small-sized dumbbell described in JIS-K-7162, by means of a small size injection molding machine (TE 3-1E, available from Nissei Resin Industries, Co., Ltd.).

[0074] The specimens were subjected to the measurements of Izod impact strength and flexural modulus. The results of the measurements together with C/A and C/B noted in Table 2 are set forth in Table 3.

TABLE-US-00003 TABLE 3 Izod impact flexural modulus C/A C/B strength (kJ/m.sup.2) (GPa) Example 5 0.0018 0.010 5.5 3.9 Example 6 0.018 0.10 6.5 3.5 Example 7 0.18 1.0 6.3 3.7 Example 8 0.88 5.0 5.2 3.6 Example 9 1.2 6.7 5.3 4.0 Example 10 1.8 10 4.8 3.7 Example 11 5.3 30 4.2 3.7 Example 12 8.8 50 3.9 3.7 Com. Ex. 3 0 0 3.7 3.5 Remarks: C/A: Amount (weight part(s)) of spherical silica particles per 100 weight parts of polypropylene resin C/B: Amount (weight part(s)) of spherical silica particles per 100 weight parts of fibrous basic magnesium sulfate particles

[0075] The results of measurements set forth in Tables 1 to 3 indicate that molded products made from polypropylene resin compositions of the invention (which are shown in Examples 1 to 12) which comprises a polypropylene resin, fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles such as spherical silica particles show enhanced Izod impact strength as compared with molded products made from the polypropylene resin compositions containing only a polypropylene resin and fibrous basic magnesium sulfate particles (which are shown in Com. Examples 1 to 3), keeping or slightly increasing the flexural modulus.