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This work aims to develop a new kind of semicrystalline polymer filament and optimize its printing parameters in the fused deposition modeling process. The purpose of this work also includes producing FDM parts with good ductility.

A new kind of semicrystalline filaments composed of long-chain polyamide (PA)1012 was prepared by controlling screw speed and pulling speed carefully. The optimal printing parameters for PA1012 filaments were explored through investigating dimensional accuracy and bonding strength of FDM parts. Furthermore, the mechanical properties of PA1012 specimens were also evaluated by varying nozzle temperatures and raster angles.

It is found that PA1012 filaments can accommodate for FDM process under suitable printing parameters. The print quality and mechanical properties of FDM parts highly depend on nozzle temperature and bed temperature. Even though higher temperatures facilitate stronger interlayer bonding, FDM parts with excellent tensile strength were obtained at a moderate nozzle temperature. Moreover, a bed temperature well above the glass transition temperature of PA1012 can eliminate shrinkage and distortion of FDM parts. As expected, FDM parts prepared with PA1012 filaments exhibit good ductility.

Results in this work demonstrate that the PA1012 filament allows the production of FDM parts with desired mechanical performance. This indicates the potential for overcoming the dependence on amorphous thermoplastics as a feedstock in the FDM technique. This work also provides insight into the effect of materials properties on the mechanical performance of FDM-printed parts.

Current literature provides limited insights into the supply chain contexts within which e-commerce can create higher value for firms. To address this literature gap, this research explores the value potential, and thus value creation process, of e-commerce initiatives for supply chain distribution channel expansions.

Using secondary data collected from multiple sources, this research conducted an event study to examine the stock market reactions to the announcements of e-commerce initiatives of Chinese firms.

The results indicate that the e-commerce initiatives increase average firm value by CNY 295.29 million in a three-day window around the initiative's announcement date. Moreover, we find that such stock market reactions are more positive for firms with poor operating performance, and more negative when firms deploy initiatives on their own (rather than third-party) platforms. Further, companies that integrate or complement their online sales with an offline sales channel experience more positive stock market reactions.

This study provides new insights into the value creation process of e-commerce from an operation and supply chain process perspective.