ABSTRACT
Sustainable polymers (SPs) are man-made polymers derived from animals, plants, and microorganisms, currently being applied in and formulated for agriculture, food, medical, pharmaceutical, packaging, sports gear, tableware, textile, etc. There is consensus among international organizations, governments, corporations, and public opinions in promoting a sustainable economy founded on sustainable materials. One of them is poly(lactic acid), a popular feedstock for additive manufacturing (AM), derived from corn starch and sugar cane.
This chapter opens with introducing polymers and plastics in general and their grades employed as feedstocks for AM. Polymers for AM fall in all the polymer families (thermosets, thermoplastics, elastomers, composites), and can be solid, liquid, fiber, powder, and sheet. Examples, features, applications, physical, and mechanical properties of commercial polymers, sustainable and not, and polymeric composite materials for conventional manufacturing and AM processes are reported, along with their price, market data and forecasts, and suppliers, in order to serve as benchmarks, indications, and guides for formulating new SPs for AM and their relative applications. The terms biomaterial, biobased, bioplastic, renewable, sustainable, degradable, biodegradable, recyclable, and compostable are defined and explained. Biobased polymers and bioplastics are introduced, and their benefits described, along with the need for them, their suppliers, market data, and predictions. Definition, examples, and benefits of SPs are included, as well as sustainability, market data and trends of AM. This chapter concludes with predictions about the near future of SPs whose expansion depends on a combination of economic, geopolitical, technological, and consumer-related factors. The diffusion of SPs is promoted by current policies and legislations at national and local level, international agreements, increasing production of SPs by world leading chemical corporations, and pro-environment public opinions, but it is hindered by their price that typically is not competitive with the price of polymers formulated from crude oil and natural gas. A wider adoption of SPs for AM in the near future of SPs for AM will be driven by the growth of the worldwide market of AM itself, investments for developing and launching new feedstocks for AM, and the preference of users of personal and industrial printers for making environmentally friendly objects. An extensive list of recent references is provided.
