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2,2,4,4-Tetramethyl-1,3-cyclobutanediol (TMCD) is a diol monomer for terephthalic acid (TPA) class of copolyesters that can increase the glass transition temperature and mechanical strength in comparison to conventional TPA polyesters. TMCD-modified poly (1,4-cyclohexylenedimethylene terephthalate) (PCTT) has been used to manufacture consumer products with good toughness, heat resistance and clarity. However, the suitability of PCTT in 3D printing had not been evaluated. Therefore, consumer plasticware was used as the starting material to investigate the suitability of this copolyester for fused deposition modeling (FDM). Chemical structure, mechanical properties, thermal behavior and viscoelastic properties of this copolyester were studied. NMR spectroscopy found that the copolyester had cyclohexanedimethanol (CHDM) and TMCD contents at 76.5 mol% and 20 mol% of total diol, respectively. 280 °C printing temperature and 110 °C bed temperature were suitable conditions for printing. Tg of PCTT was 103 °C (25 °C higher than PETG). Young's modulus and impact strength of printed PCTT were at least 100% and 65% higher than printed PETG, respectively. The ease of printing, superior mechanical properties and Tg (103 °C) make the PCTT random copolyester highly applicable in additive manufacturing.

The Apitong wood species has long been the most popular choice for transportation, such as in trailer decking and shipping container floors. However, Apitong is depleting due to its excessive usage. Bamboo fiber provides as an alternative due to its low density (608–780 kg/m3) and lightweight attributes. This study explores 1) development and properties of bamboo-thermoplastic composites with different fiber content, and 2) application of bamboo composite in trailer decking (a transportation application) as an alternative to Apitong. Extrusion-compression and compression molding was used as processing approaches for the bamboo-thermoplastic composites. The basic panels were tested for flexural loading and nail pull out to evaluate the feasibility as a viable trailer decking material. The flexural strength and modulus of bamboo composite were found to be 17 and 98% higher than Apitong, respectively. The density of the bamboo-thermoplastic was 670 kg/m3 compared to Apitong (737 kg/m3), hence 10% lighter. The nail pull-out strength was comparable between the two. The work progressed to producing prototype trailer decking members via extrusion-compression and compression molding. The bamboo-composite decking was evaluated on a trailer test bed and exhibited excellent surface wear response, minimal internal damage and withstood 400 fatigue cycles with onset of failure only at the supports, which the span did not exhibit damage.