8445
Molecular nonwoven fabrics in the form of ultrathin layer - by - layer ( LbL ) helical polymer films with covalent cross - linking were assembled on substrates by an alternate ester - amide exchange reaction between poly ( gamma - methyl l - glutamate ) ( PMLG ) and cross - linking agent ethylene diamine or 4 , 4 ' - diamino azobenzene .
 Chemical: ester; Chemical: amide; Chemical: poly ( gamma - methyl l - glutamate ); Chemical: PMLG; Chemical: ethylene diamine; Chemical: 4 , 4 ' - diamino azobenzene
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: ester; Chemical: amide; Chemical: poly ( gamma - methyl l - glutamate ); Chemical: PMLG; Chemical: ethylene diamine; Chemical: 4 , 4 ' - diamino azobenzene