All plastics are made of polymers, and many of these polymers are especially suitable for use in biomedical implants and drug delivery devices.
Materials have played a central role in our history, so much so that they define the various epochs of human civilization, such as Stone, Bronze, and Iron Ages. An archeologist hundreds of years from now might well define the period that we are living through as the age of plastics. They might as well cite the movie The Graduate (1967), in which a young college graduate receives one word of career advice - “Plastics”- , to pinpoint when this age began. All plastics are made of polymers, and many of these polymers are especially suitable for use in biomedical implants and drug delivery devices. Unlike metals and ceramics, polymers possess properties that are, with a few exceptions, similar to those of our organs and tissues. Like proteins that make up our tissues, polymers are made of many repeating units that are strung like beads on a necklace.
Many scientists have worked over the past hundred years to make miraculous materials based on this simple concept, and some have received Nobel prizes. Their work has shown that the weak forces that hold the polymer chains together can make polymers be as soft as a hydrogel, while the strong forces that hold the beads along the chain can make them be as strong as steel. Polymer chemists and physicists have devised elegant theories to explain and predict how molecules move around either randomly or in unison when they are subjected to mechanical forces. They have invented instruments to see how material properties can be manipulated by solvents or heat, so that they can be coerced to become nanospheres for use as drug carriers, or enticed to transform themselves into strong bone scaffolds to repair critical gaps, which may make prosthetic limbs unnecessary. Basic research in polymer physics and chemistry, and applied efforts in engineering continue to develop new tissue and organ replacements that mimic nature.
