19518
Functionalizing the pi - cores with " alkyl chains " is a common strategy in the molecular design that can give the system desirable properties , such as good solubility in organic solvents for solution processing .
 Chemical: alkyl
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: alkyl