10647
Upon oxidation and reduction , these covalently interconnected layers do not disassemble , in contrast to poly ( ferrocenylsilane ) ( PFS ) layers featuring similar backbone structures that are held together by electrostatic forces .
 Chemical: poly ( ferrocenylsilane ); Chemical: PFS
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: poly ( ferrocenylsilane ); Chemical: PFS