Need help with microshear bands in polymers

[Monk80]

This is my first post. I have a paper due on microshear banding in polymers. I have found lots of papers on the subject, but nowhere have I found a straightforward explanation of what is the underlying cause of these bands. What changes in structure are causing the bands, and what effects do they have for the bulk polymer?

 

[chemisttree]

Is http://books.google.com/books?id=GK...sult&ct=result&resnum=2#v=onepage&q=&f=false" any help?