A material that is used in some end product and then discarded passes through several stages or phases, which is sometimes termed the total materials cycle or just materials ______ and represents the “cradle-to-grave” life circuit of a material.
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Sustainability represents the ability to maintain an acceptable lifestyle at the present level and into the indefinite future while preserving the ______ .
Recyclable means that a material, after completing its life cycle in one component, could be ______ , could reenter the materials cycle, and could be reused in another component—a process that could be repeated an indefinite number of times.
By completely biodegradable, we mean that, by interactions with the environment (natural chemicals, microorganisms, oxygen, heat, sunlight, etc.), the material deteriorates and returns to virtually the ______ state in which it existed prior to the initial processing. Engineering materials exhibit varying degrees of recyclability and biodegradability.
The tensile plastic deformation of spherulitic polymers occurs in several stages as both amorphous tie chains and chain-folded block segments (which separate from the ribbon-like lamellae) become oriented with the ______ axis.