Polymer morphology is the overall form of polymer structure, including crystallinity, branching, molecular weight, cross-linking, and so on. Small molecules usually have crystalline solids, which are highly-ordered 3-dimensional arrays of the molecules. Solid polymers can be crystalline or amorphous (disordered arrangements of randomly coiled and entangled chains). Thermoplastics usually are semicrystalline - a combination of crystalline and amorphous regions. The properties of thermoplastics are strongly influenced by their morphology.
David Whisnant (Wofford College). Partial support for this work was provided by the National Science Foundation's Division of Undergraduate Education through grants DUE #9950809 and DUE #9950296. Additional support was provided by the Camille and Henry Dreyfus Foundation.