Carbon fiber bundle, process for producing the same, and thermoplastic resin composition and molded article thereof

Abstract

A carbon fiber bundle is provided which can develop satisfactory interfacial adhesion to polyolefin-based resins, especially polypropylene resins. The carbon fiber bundle comprises a plurality of single fibers that was sized with a sizing agent comprising: a polymer having a main chain formed of carbon-carbon bonds, containing an acid group in at least part of side chains or at least a part of main chain ends, and representing an acid value of 23 to 120 mgKOH / g as measured in accordance with ASTM D1386; or a polymer having a main chain formed of carbon-carbon bonds and containing at least either of an epoxy group and an ester group in at least a part of side chains or at least a part of main chain ends.

Description

technical field

[0001] The present invention relates to a carbon fiber bundle used as a reinforcing material for a thermoplastic resin and a method for producing the same. It also relates to a thermoplastic resin composition using these carbon fiber bundles and a molded article thereof. Background technique

[0002] The so-called carbon fiber bundle is a carbon fiber bundle in which a plurality of single fibers made of carbon are gathered together and used as a reinforcing material such as a thermoplastic resin.

[0003] When used as a reinforcing material of thermoplastic resin, carbon fiber bundles are generally supplied in a form cut into a length of 5 to 15 mm. When producing pellets kneaded with the carbon fiber bundles and the thermoplastic resin, it is necessary to supply the carbon fiber bundles to the extruder in a fixed amount, and thus the morphological stability of the carbon fiber bundles is important. If the shape is not suitable, it will cause spit spots. I...

Examples

Embodiment 1～13、 comparative example 1～3

[0162]

[0163] 68 parts by mass of polypropylene resin (EPR copolymerized polypropylene, trade name: J-5051HP, manufactured by Idemitsu Petrochemical Co., Ltd.) and 12 parts by mass of modified polypropylene resin (Malaysia Co., Ltd. Anhydride copolymerized polypropylene high-concentration dyeing compound P503, manufactured by Mitsubishi Chemical Corporation), supplied 20 parts by mass of carbon fiber bundles shown in Tables 6 and 7 from a side feeder and kneaded to obtain pellets of a thermoplastic resin composition. Here, in all cases, no stagnation was seen in the twin-screw extruder.

[0164] The pellets of the thermoplastic resin composition obtained were formed into molded products using a 20 mm, 35 oz screw linear molding machine under conditions of a cylinder temperature of 250°C and a mold temperature of 60°C. The mechanical properties of the obtained molded articles are shown in Tables 6 and 7. It can be seen that the molded articles of Examples 1 to 13 are supe...

Embodiment 14、15

[0167] Embodiment 14, 15, comparative example 4

[0168]

[0169] 80 parts by mass of polypropylene resin (EPR copolymerized polypropylene, trade name: J-5051HP, manufactured by Idemitsu Petrochemical Co., Ltd.) was supplied to a twin-screw extruder heated to 250° C., and 20 parts by mass of a table were supplied from a side feeder. The carbon fiber bundles shown in 8 were kneaded to obtain pellets of the thermoplastic resin composition. Here, in all cases, no stagnation was seen in the twin-screw extruder.

[0170]The pellets of the thermoplastic resin composition obtained were formed into molded products using a 20 mm, 35 oz screw linear molding machine under conditions of a cylinder temperature of 250°C and a mold temperature of 60°C. Table 8 shows the mechanical properties of the obtained molded articles. It can be seen that the molded products of Examples 14 and 15 are superior in tensile breaking strength, flexural strength, and Izod impact strength compared to the ...

technical field

[0001] The present invention relates to a carbon fiber bundle used as a reinforcing material for a thermoplastic resin and a method for producing the same. It also relates to a thermoplastic resin composition using these carbon fiber bundles and a molded article thereof. Background technique

[0002] The so-called carbon fiber bundle is a carbon fiber bundle in which a plurality of single fibers made of carbon are gathered together and used as a reinforcing material such as a thermoplastic resin.

[0003] When used as a reinforcing material of thermoplastic resin, carbon fiber bundles are generally supplied in a form cut into a length of 5 to 15 mm. When producing pellets kneaded with the carbon fiber bundles and the thermoplastic resin, it is necessary to supply the carbon fiber bundles to the extruder in a fixed amount, and thus the morphological stability of the carbon fiber bundles is important. If the shape is not suitable, it will cause spit spots. I...

Examples

Embodiment 1～13、 comparative example 1～3

[0162]

[0163] 68 parts by mass of polypropylene resin (EPR copolymerized polypropylene, trade name: J-5051HP, manufactured by Idemitsu Petrochemical Co., Ltd.) and 12 parts by mass of modified polypropylene resin (Malaysia Co., Ltd. Anhydride copolymerized polypropylene high-concentration dyeing compound P503, manufactured by Mitsubishi Chemical Corporation), supplied 20 parts by mass of carbon fiber bundles shown in Tables 6 and 7 from a side feeder and kneaded to obtain pellets of a thermoplastic resin composition. Here, in all cases, no stagnation was seen in the twin-screw extruder.

[0164] The pellets of the thermoplastic resin composition obtained were formed into molded products using a 20 mm, 35 oz screw linear molding machine under conditions of a cylinder temperature of 250°C and a mold temperature of 60°C. The mechanical properties of the obtained molded articles are shown in Tables 6 and 7. It can be seen that the molded articles of Examples 1 to 13 are supe...

Embodiment 14、15

[0167] Embodiment 14, 15, comparative example 4

[0168]

[0169] 80 parts by mass of polypropylene resin (EPR copolymerized polypropylene, trade name: J-5051HP, manufactured by Idemitsu Petrochemical Co., Ltd.) was supplied to a twin-screw extruder heated to 250° C., and 20 parts by mass of a table were supplied from a side feeder. The carbon fiber bundles shown in 8 were kneaded to obtain pellets of the thermoplastic resin composition. Here, in all cases, no stagnation was seen in the twin-screw extruder.

[0170]The pellets of the thermoplastic resin composition obtained were formed into molded products using a 20 mm, 35 oz screw linear molding machine under conditions of a cylinder temperature of 250°C and a mold temperature of 60°C. Table 8 shows the mechanical properties of the obtained molded articles. It can be seen that the molded products of Examples 14 and 15 are superior in tensile breaking strength, flexural strength, and Izod impact strength compared to the ...