3511
A reactive filament comprising of a polyvinylidene fluoride ( PVDF ) binder with 20 % mass loading of aluminum ( Al ) was prepared using a commercial filament extruder and printed using a Makerbot Replicator 2X .
 filament, binder, aluminum, Al, filament, extruder
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 filament, binder, aluminum, Al, filament, extruder