Are paper cups really made of paper?

The secret of a paper cup…

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.


  • drain clean­er;
  • glass cup;
  • pa­per cup;
  • plas­tic stick.

Step-by-step in­struc­tions

Pour some drain clean­er into a glass and im­merse a pa­per cup in it. Af­ter an hour, take the cup out and use a plas­tic stick to clean off the yel­lowed pa­per and re­veal… plas­tic!

Process de­scrip­tion

The sodi­um hy­drox­ide in the drain clean­er de­stroys the pa­per’s struc­ture, mak­ing it easy to clean away. This re­veals the plas­tic film un­der it, which pre­vents the pa­per from get­ting wet and the bev­er­age from leak­ing. The film is made of poly­eth­yl­ene, so this "pa­per" cup can not be re­cy­cled with reg­u­lar pa­per. It re­quires sep­a­rate col­lec­tion and spe­cial pro­cess­ing.

Cool ex­per­i­ments are wait­ing for you in the MEL Chem­istry sub­scrip­tion!