Master batch containing acylation-modified microfibrillated plant fibers

A method for producing a master batch comprising acylated, microfibrillated plant fibers (A), a thermoplastic resin (B), and a compatibilizer (C),

• wherein the master batch excludes alkyl or alkenyl succinic anhydride-modified plant fibers and microfibrillated plant fibers, and
• the master batch being for use in the production of a fiber-reinforced resin composition by mixing with a resin for dilution (D),
• the method comprising the step of
• melt-kneading acylated plant fibers (A′) as a raw material of acylated, microfibrillated plant fibers (A), a thermoplastic resin (B), and a compatibilizer (C) to defibrate the acylated plant fibers (A′) in a melt-kneaded product while melt-kneading,
• wherein the following conditions are satisfied:
• (a) the acylated, microfibrillated plant fibers (A) have a solubility parameter (SPacylmf) of 10 or more and are modified with an acyl group represented by the formula R—CO— wherein R represents an alkyl group having 1 to 5 carbon atoms;
• (b) the thermoplastic resin (B) has a solubility parameter (SPpm) of 9 to 15, and the solubility parameter (SPpm) is greater than the solubility parameter (SPpd) of the resin for dilution (D);
• and
• (c) the compatibilizer (C) has a solubility parameter (SPcom) equal to or less than the solubility parameter (SPacylmf) of the acylated, microfibrillated plant fibers (A).

A method for producing a master batch comprising acylated, microfibrillated plant fibers (A), a thermoplastic resin (B), and a compatibilizer (C),

• wherein the master batch excludes alkyl or alkenyl succinic anhydride-modified plant fibers and microfibrillated plant fibers, and
• the master batch being for use in the production of a fiber-reinforced resin composition by mixing with a resin for dilution (D),
• the method comprising the steps of:
• (1) melt-kneading acylated plant fibers (A′) as a raw material of acylated, microfibrillated plant fibers (A) and a thermoplastic resin (B) to defibrate the acylated plant fibers (A′) in a melt-kneaded product while melt-kneading to obtain a melt-kneaded product containing the acylated, microfibrillated plant fibers (A),
• wherein the following conditions are satisfied:
• (a) the acylated, microfibrillated plant fibers (A) have a solubility parameter (SPacylmf) of 10 or more and are modified with an acyl group represented by R—CO— wherein R represents an alkyl group having 1 to 5 carbon atoms;
• and
• (b) the thermoplastic resin (B) has a solubility parameter (SPpm) of 9 to 15, and the solubility parameter (SPpm) is greater than the solubility parameter (SPpd) of the resin for dilution (D), and
• (2) adding a compatibilizer (C) to the melt-kneaded product containing the acylated, microfibrillated plant fibers (A) obtained in step (1) to further perform melt-kneading, wherein the following condition is satisfied:
• (c) the compatibilizer (C) has a solubility parameter (SPcom) equal to or less than the solubility parameter (SPacylmf) of the acylated, microfibrillated plant fibers (A).