Syllabus

3.91 Mechanical Properties of Plastics is one of MIT's principal graduate subjects in polymeric materials. It is a "core" subject in the doctoral Polymer Program of the Department of Materials Science and Engineering, and also the MIT interdepartmental Program in Polymer Science and Technology (PPST). 3.91 was developed originally by Prof. F. J. McGarry in the 1960's, and has been offered continually at MIT ever since. Prof. D. Roylance has co-taught the subject since the mid-1970's, and became the sole instructor with Prof. McGarry's retirement in June 2002.
 
As its name implies, 3.91 is aimed at presenting the concepts underlying the response of polymeric materials to applied loads. These will include both the molecular mechanisms involved and the mathematical description of the relevant continuum mechanics. It is dominantly an "engineering" subject, but with an atomistic flavor. The subject content will follow approximately that of the Ward text:
  • Polymer structure
  • Deformation of elastic solids
  • Rubber-like elasticity
  • Linear viscoelasticity
  • Composite materials and laminates
  • Yield
  • Fracture

The subject carries 3-0-9 credit, so approximately three hours of outside work should follow each lecture hour. These outside hours will include a thorough reading of various sections of the Ward text or Roylance modules as assigned in the Schedule, and often one or more engineering problems. The reading assigned for a given day should be complete before class, and the assigned problem should be turned in at the next class meeting. (Occasionally your personal schedule may force you to delay a day or two, but try to avoid this.) No penalty will be assessed for the occasional late submission. Grading will be based on the quality of the submitted problems, the vigor of your in-class discussion, and the three quizzes.
 
Student collaboration on homework is permitted and encouraged, but all work to be submitted should then be worked out and written up on your own. Copying from "bibles" or other such sources is cheating. Computer solutions are encouraged when appropriate; Maple is excellent for many of the assigned problems.

There are no formal recitations, but you are encouraged to make frequent use of the Instructor's office hours for assistance or just informal discussion.