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Nowadays, there are many types of 3D printer filaments have been produced to fulfill the demand of small-scale fabrication industry. The use of polymer biocomposites as 3D printer filaments is one of the ways to reduce the depend-ence on the synthetic thermoplastics that are expensive and non-biodegradable. This is due to the utilization of natural fibers as fillers that can decrease the percentage of synthetic thermoplastics usage. Nevertheless, there are some criteria must be considered to ensure the quality of the 3D printed products fabricated from the biocomposites is good as existing filaments. This paper has briefly explained some important criteria that recently identified before preparing 3D printer filaments from polymer biocomposites.

Polymer orientation is generally known as an alignment of polymer molecular chains in solid state. It is a unique phenomenon which takes places in each moulding process. The long-chain molecules of polymer will flow in molten state and harden in the mould in certain orientation. It is known that the orientation of polymer in the thermoplastic products is not very crucial because there is no reinforced filler in the systems that can significantly influence their mechanical properties.

An ionic liquid, 1-n-butyl-3-methylimidazolium chloride (BmimCl) was blended with urea at 1:1 mole ratio to create a BmimCl/Urea mixture. The agarose/talc composite films containing the BmimCl/Urea mixture were then acquired through a gelation method. The weight ratio of agarose and talc was fixed at 4:1, while the content of BmimCl/Urea was varied from 0 to 10 wt % relative to the overall weight of the composite films. The tensile stress and modulus results showed the optimum BmimCl/Urea content in the composite film lies at 8 wt %. The talc particles are embedded in the agarose matrix and there are no pullouts for the composite films containing BmimCl/Urea as demonstrated by SEM micrographs. The addition of BmimCl/Urea increased the glass transition temperature of the composite films, however, the thermal decomposition temperature decreased drastically. FTIR and FT-Raman spectra indicated the existence of interaction between agarose and talc, which improves their interfacial adhesion. As a conclusion, a BmimCl/Urea mixture can be utilized as a coupling agent for agarose/talc composite films.

In this study, we are interested in the eutectic processing of chloride compounds, and decided to focus on ammonium based compounds that can provide sufficient insight in the fundamental chemistry. 14 types ammonium based chloride compounds namely ammonium chloride, methanaminium chloride, dimethylammonium chloride, trimethylammonium chloride, tetramethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, carboxytrimethylmethanaminium chloride, phenyltrimethylammonium chloride, benzyltrimethylammonium chloride, (vinylbenzyl)trimethylammonium chloride, 2-acetoxytrimethylethanaminium chloride, (2-acetoxypropyl)trimethylammonium chloride and 2-(benzoyloxy)trimethylethanaminium chloride were used in this study. This research led to a hypothesis that the ammonium based chloride compounds could be react with the urea by complexing the hydrogen groups that are hydrogen bond donor giving eutectic mixtures. However, functional groups have plays an important role to influence thermal properties of those eutectic mixtures. This is regarded to be a motivating finding that will be important to most future research work involving complexation reaction for the production of eutectic mixtures.

4-formyl-N,N-dimethylbenzenaminium chloride (FDBC), carboxymethanami-nium chloride (CMAC), 1,3-dihydroxy-2-(hydroxymethyl)propan-2-aminium chloride (DHPC), (R)-1-carboxy-2-mercaptoethanaminium chloride (CMEC) and 1-methyl-2-oxopyrrolidinium chloride (MOPC) were synthesised and complexed with either urea or oxalic acid at different molar ratios to form protic eutectic ionic liquids (PEILs). The melting point of the PEILs was measured using differential scanning calorimetry (DSC). Based on the melting point results, MOPC complexed with oxalic acid ([MOPC][O]) at a 1:1 molar ratio and DHPC complexed with urea ([DHPC][U]) at a 1:2 molar ratio were regarded as room temperature ionic liquids (RTILs). The solubility study showed that [MOPC][O] was able to fully dissolve soluble starch and rice starch (10 wt%) and partially dissolve sago starch.

In this study, lignin was isolated from rubber wood by means of ionic liquid (1,3-dimethylimidazolium methylsulfate). The optimum parameters to isolate lignin were investigated which include the concentrations of ionic liquid (0.1, 0.2, 0.3, 0.4, 0.5 moles), isolation durations (30, 60, 90, 120, 150 minutes), and isolation temperatures (25, 40, 60, 80, 100°C). The optimum parameters for lignin isolation are 0.5 moles concentration, 120 minutes and 100°C. Lignin could be isolated from rubber wood up to 13.03wt.% by ionic liquid however, in comparison with acid and alkaline isolation, they give better yields than ionic liquid which 22.15wt.% and 1 8.56wt.% of lignin, respectively. Lignin preliminary structures isolated by ionic liquid have been confirmed based on Fourier transform infrared (FTIR) results. From these results, isolated lignin by ionic liquid provides lignin without other related isolative. Apart from that, ionic liquid also could be recycled up to three times compared to acid and alkaline isolation methods.