14267
Specifically , a series of PDMS coatings containing either a QAS with a single ammonium salt group per molecule or a quaternary ammonium - functionalized polyhedral oligomeric silsesquioxane ( Q - POSS ) were measured with SFG in air , water , and artificial seawater ( ASW ) to investigate the relationships between the interfacial surface structures of these materials and their antifouling properties .
 Chemical: PDMS; Chemical: ammonium; Chemical: ammonium; Chemical: polyhedral oligomeric silsesquioxane; Chemical: POSS
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: PDMS; Chemical: ammonium; Chemical: ammonium; Chemical: polyhedral oligomeric silsesquioxane; Chemical: POSS