%SUBJECT: File CHEMF11.TEX
 
\newbox\monomera\setbox\monomera=
\structure{\nopositioncheck\esingle\atom{C}
\side{\nsingle\atom{C}\epin{H$_3$}}
\atom{H}\esingle\atom{CH$_2$}}
\newbox\monomerb\setbox\monomerb=
\structure{\nopositioncheck\esingle\atom{C}
\side{\ssingle\atom{C}\epin{H$_3$}}
\atom{H}\esingle\atom{CH$_2$}}
\newbox\monomere\setbox\monomere=
\structure{\nopositioncheck\esingle\atom{C}
\side{\nsingle\atom{C}\epin{H$_3$}}
\atom{H}\esingle\atom{CH$_2$}\esingle\phantatom{}}
\vbox{
\centerline{\copy\monomera\copy\monomera\copy\monomera\copy\monomera
\copy\monomera\copy\monomera\copy\monomere}
\vskip 1truecm
\centerline{\copy\monomera\copy\monomerb\copy\monomera\copy\monomerb
\copy\monomera\copy\monomerb\copy\monomere}
\vskip 1truecm
\centerline{\it Fig.~11: Isotactic and syndiotactic polypropylene}
}