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Experimentation is conducted to process polyethylene terephthalate bottles and packaging into filament that can then be used for additive manufacturing methods like fused filament fabrication , without the use of additives or modification to the polymer .
 concept or principle: process; material: polyethylene terephthalate; material: filament; material: be; manufacturing process: additive manufacturing; manufacturing process: fused filament fabrication; material: additives; material: polymer
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: 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} 
 Entities: process, polyethylene terephthalate, filament, be, additive manufacturing, fused filament fabrication, additives, polymer 
Answer:
 concept or principle: process; material: polyethylene terephthalate; material: filament; material: be; manufacturing process: additive manufacturing; manufacturing process: fused filament fabrication; material: additives; material: polymer