The material now known as Super Glue was discovered in 1942 by Dr. Harry Coover, who was experimenting with different materials for the manufacture of plastic gun sights. He rejected the material, cyanoacrylates, for the project because it stuck to everything. In 1951, Coover and fellow scientist Fred Joyner rediscovered the material while working for Eastman Kodak. Today, Super Glue fixes everything from busted pottery and split fingernails to broken doll pieces and crafts. When it dries, the glue is difficult, but not impossible, to remove. On plexiglass, for example, there are ways to loosen the substance and clean the surface so that it looks like new.
Clean the surface with a soft cloth to remove any dirt or debris. Place one hand on the plexiglass and hold the razor blade in the other. Gently place the razor blade between the glass and dried glue and pull upward to dislodge. Continue this motion until the largest pieces of glue are lifted.
Wipe the surface clean with a soft cloth. Poor 4 tbsp. of acetone in a small, shallow dish. Dip the toothbrush bristles into the acetone. Gently brush the plexiglass where the remainder of the glue resides. Wipe clean with a damp cloth.
Squeeze the juice of one lemon onto any glue that remains. Let sit for three minutes. Sprinkle salt onto the lemon juice and let sit for five minutes. Wipe the mixture off the glass with a dry cloth.
Squeeze 1/2 tsp. dish detergent into a bowl and fill with water to create suds. Dip a clean cloth into the mixture and gently rub the glass surface in circles. Rinse the cloth with warm water. Ring out the excess water and wipe the glass again to remove the excess detergent. Wipe area clean with a dry cloth.