The masterbatch contains a black pigment and a masterbatch thermoplastic resin, the masterbatch satisfying the following conditions: (Conditions) when a resin plate is produced by kneading 100 parts by weight of polypropylene having a melt flow rate of 30 g/10 min (JIS K7210:1999) and a density of 0.9 g/cm.sup.3 (JIS K7112:1999) with respect to 3 parts by weight of the masterbatch and subjecting the mixture to injection molding using a mold polished by a coated abrasive with a particle size of #800 (JIS R6001:1998), a* values and b* values of a surface of the resin plate in the L*a*b* color system satisfy specific conditions.

A method for producing a rubber wet masterbatch includes mixing a rubber latex solution and a coagulant with a carbon black-containing slurry aqueous solution in which a carbon black is dispersed in water, to produce a carbon black-containing rubber latex aqueous solution having a pH of 7 to 8.5; adding additional coagulant to the carbon black-containing rubber latex aqueous solution obtained to produce a carbon black-containing rubber coagulum; and dehydrating and drying the carbon black-containing rubber coagulum obtained to produce a rubber wet masterbatch, wherein a rubber component contained in the rubber latex solution is added at an addition rate of 10 g/min or more and 100 g/min or less and the part of the coagulant is added at an addition rate of 10 mmol/min or more and 100 mmol/min or less per 100 g of the carbon black contained in the carbon black-containing slurry aqueous solution.

A method for producing a rubber wet masterbatch includes mixing a rubber latex solution and a coagulant with a carbon black-containing slurry aqueous solution in which a carbon black is dispersed in water, to produce a carbon black-containing rubber latex aqueous solution having a pH of 7 to 8.5; adding additional coagulant to the carbon black-containing rubber latex aqueous solution obtained to produce a carbon black-containing rubber coagulum; and dehydrating and drying the carbon black-containing rubber coagulum obtained to produce a rubber wet masterbatch, wherein a rubber component contained in the rubber latex solution is added at an addition rate of 10 g/min or more and 100 g/min or less and the part of the coagulant is added at an addition rate of 10 mmol/min or more and 100 mmol/min or less per 100 g of the carbon black contained in the carbon black-containing slurry aqueous solution.

Provided is a method with which a biodegradable polyester film containing polyhydroxyalkanoate can be stably produced by film blowing under practical processing conditions. A method for producing a biodegradable polyester film containing a biodegradable aliphatic polyester (A) and a fatty acid amide (B) by film blowing, the biodegradable aliphatic polyester (A) containing polyhydroxyalkanoate, the method including: a step (I) of dry-blending the biodegradable aliphatic polyester (A) with a masterbatch containing the fatty acid amide (B) and a base material resin; and a step (II) of subjecting the mixture obtained in the step (I) to film blowing.

Provided is a method with which a biodegradable polyester film containing polyhydroxyalkanoate can be stably produced by film blowing under practical processing conditions. A method for producing a biodegradable polyester film containing a biodegradable aliphatic polyester (A) and a fatty acid amide (B) by film blowing, the biodegradable aliphatic polyester (A) containing polyhydroxyalkanoate, the method including: a step (I) of dry-blending the biodegradable aliphatic polyester (A) with a masterbatch containing the fatty acid amide (B) and a base material resin; and a step (II) of subjecting the mixture obtained in the step (I) to film blowing.

An opacified polymeric composition including a first polymer having a first refractive index; a second polymer having a second refractive index, wherein the second refractive index of the second polymer is lower than the first refractive index of the first polymer; a light scattering inorganic additive; a light absorbing additive; and a light reflecting additive.

An opacified polymeric composition including a first polymer having a first refractive index; a second polymer having a second refractive index, wherein the second refractive index of the second polymer is lower than the first refractive index of the first polymer; a light scattering inorganic additive; a light absorbing additive; and a light reflecting additive.

A vulcanizing agent-modified graphene prepared through an in-situ chemical deposition process and a controllable crosslinked natural rubber composite containing the same. In the preparation of the vulcanizing agent-modified graphene, graphene oxide is coated on a spherical thermal-conductive functional particle through the chemical bonding to obtain a 3D graphene particle; and a vulcanizing agent is adsorbed on the 3D graphene particle through π-π conjugation by an in-situ chemical deposition process to obtain a vulcanizing agent-modified graphene particle. Further, the vulcanizing agent-modified graphene particle is mixed with natural rubber latex, and undergoes synergistic coagulation in water to form a graphene masterbatch, which is further processed into the controllable crosslinked natural rubber composite by adding a certain amount of natural rubber block, rubber additive and reinforcing filler.

A method for producing a molding compound having improved surface properties is provided. The method relates to, in particular, a molding compound comprising a polycarbonate and at least one reinforcing filler, preferably selected from the group including titanium dioxide (TiO.sub.2), talc (Mg.sub.3Si.sub.4O.sub.10(OH).sub.2), dolomite CaMg[CO.sub.3].sub.2, kaolinite Al.sub.4[(OH).sub.8|Si.sub.4O.sub.10] and wollastonite Ca.sub.3[Si.sub.3O.sub.9], preferably selected from the group including titanium dioxide (TiO.sub.2) and talc (Mg.sub.3Si.sub.4O.sub.10(OH).sub.2). The total amount of reinforcing filler is 3 to 20 wt. %, preferably 4.5 to 15 wt. %, each relative to the total mass of the molding compound, the molding compound having improved properties being produced using at least one master batch produced according to the method.

The invention relates to a method for producing a polymer master batch and a polymer composition, wherein the method comprises providing at least one monomer capable of forming a poly(hydroxy carboxylic acid), providing a graphene nano-filler, mixing the monomer and the graphene nano-filler and letting the monomer polymerize in the presence of the graphene nano-filler. The polymer together with the graphene nano-filler is further blended with another polymer to form a polymer composite. The invention also relates to a polymer composition with graphene nano-filler and a composite material comprising a polymer composite with graphene nano-fillers.