- Acetone will dissolve the polymer and the gas escapes from the foaming agent. Then, the polymer becomes smaller and denser when the gas escapes.
- LDPE cannot be used in the circumstance as it is not strong enough to withstand the potential pressures it would be subjected to. HDPE on the other hand is a much stronger polymer because of the way the layers of monomers are arranged. Using a thin layer of HDPE overcomes the its rigidity allows the gloves to be tough as well as flexible.
- No it does not. This occurs in plastic because the intermolecular bonds between the layers of plastic are weak enough to cause them to slide over one another. This ability is not facilitated by the rigid intermolecular bonds in paper (as it is not a pure polymer) Hence the paper does not exibit this property of stretching under pressure.
- First, it has to be non-toxic so that it does not adversely affect the patient. Next, it cannot be soluble as the human body contains water, fats and other solutions that could compromise the structural integrity of the implant. Also, it has to be stable once implanted into the body. Lastly, it should not be too expensive so that it can be available to the majority of patients. Contact lenses are made from PMMA, an early polymer developed specifically for this purpose. RGP and HEMA are also used in newer designs. Contact lenses should be non-toxic, clear, permeable to oxygen and comfortable to wear. Hard contact lenses are made from PMMA and are made to be more lasting. Soft contact lenses are based on silicon polymers which tend to be more comfortable and more permeable to oxygen.
We may not be the brightest but we are the coolest.