9307
However , synthetic routes to acetal - containing PEGs published up to date either require enormous efforts or result in ill - defined materials with a lack of control over the molecular weight .
 Chemical: acetal; Chemical: PEGs
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: acetal, PEGs 
Answer:
 Chemical: acetal; Chemical: PEGs