▎ 摘　　要

NOVELTY - Producing polymer composite involves: (a) providing at least one monomer capable of forming a poly(hydroxy carboxylic acid); (b) providing a graphene nano-filler; (c) mixing the monomer capable of forming a poly(hydroxy carboxylic acid) and the graphene nano-filler; (d) optionally providing component selected from 2nd monomer capable of forming a polymer, an adjuvant, an additive and a catalyst; (e) letting the monomer capable of forming a poly(hydroxy carboxylic acid) polymerize in the presence of the graphene nano-filler; (f) introducing polymer master batch into an extruder together with another polymer which is the same or different compared to the polymer in the master batch to form a polymer composite. The graphene nano-filler is a multi-walled carbon nanotube (mwcnt) or a single wall carbon nanotube (swcnt) (preferred), and content of the graphene nano-filler in the formed polymer composite is 0.001-0.3 wt.%, preferably 0.01-0.1 wt.%. USE - The method is useful for producing polymer composite. The polymer composite, the polymer material, or the composite material is useful for forming strands, fibers or pellets, which can be formed into a blown film, cast film or molded into a suitable object; and useful as raw material in three dimensional (3-D) printing (all claimed). ADVANTAGE - The polymeric material is a biodegradable polymer with conductive properties. The conductive biodegradable polymer material has sustained or improved properties compared to non-conductive polymer materials. The in situ polymerization of the poly(hydroxy carboxylic acid) in the presence of graphene nano-fillers provides a master batch where the graphene nano-fillers have an improved distribution and dispersion in the polymer. This improved distribution and dispersion of the graphene nano-fillers in the polymer compared to polymers, where the nano-fillers have been mixed or blended in the melted polymer, provides significantly improved over all properties. Sufficient conductivity can be reach with very low amount of nano-fillers and the low amount does not infer with the other properties of the poly(hydroxy carboxylic acid). The method can impart conductivity to poly(hydroxy carboxylic acid)s using fillers without the need to compromise on any other properties of the polymer composition. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a polymer composite comprising a biodegradable poly(hydroxy carboxylic acid) and a graphene nano-filler, which imparts electric conductivity to the polymer composite, where the amount of graphene nano-fillers in the polymer composite is 0.001-0.3 wt.%, preferably 0.001-0.1 wt.% and more preferably 0.01-0.05 wt.% and the graphene nano-filler is mwcnt or swcnt, preferably a single wall carbon nanotube; (2) a polymer material comprising at least a polymer composite and optionally a second biodegradable polymer and additives selected from, dyes, plasticizers, antistatic agents, extenders, flame retardants, heat stabilizers, pigments and mixture; and (3) a composite material comprising a polymer composite, comprising a concentration of graphene nano-fillers at 0.001-1 wt.% and another component selected from wollastonite, talc, mica, graphene, graphite, degradable glass fiber and mixture.