Answer:

mylar

Answer	Crossword Clue
MYLAR	Balloon material
MYLAR	Floppy disk material
MYLAR	Reflective material for helium balloons

MYLAR	Recording-tape polyester brand
MYLAR	Helium-balloon material
MYLAR	Strong polyester film
MYLAR	Polyester film trademark
MYLAR	Polyester film brand
MYLAR	Collectible comic book protection
MYLAR	Polyester sheet
MYLAR	Shiny balloon material

MYLAR	Long-lasting balloon material
MYLAR	Birthday-balloon material
MYLAR	Trademark in the film business
MYLAR	Helium balloon material
MYLAR	Film used for recording tapes
MYLAR	Insulation material
MYLAR	Solar sails material
MYLAR	Reflective material

MYLAR	Space blanket material
MYLAR	Shiny balloon polyester