CM8001

Styrofoam is expanded polystyrene. When styrofoam is treated with acetone, the acetone collapses the physical structure of styrofoam. The air trapped within styrofoam is released when acetone is added.

A) if branches HDPE is used, the packing of HDPE would not be compact which will contribute to a certain degree of softness to the gloves. This might lower the strength and the resistance of gloves to being cut.
B) HDPE molecules must align in a manner that produces the necessary strength. Using a thin liner of HDPE allows efficient flexibility.

When plastic ages being stretched, molecules move so t hat they are more aligned to the direction where they are being pulled towards. If bag is stretched sufficiently, an almost complete alignment is reached causing a neck to form. The neck has a nearly crystalline structure.

Paper is made of fibers called cellulose. Cellulose are stuck together with lignin, a natural glue. The cellulose fibers can only be separated when lignin is removed. Therefore, paper cannot be stretched easily.

A) will not evoke a sustained inflammatory response, produce non toxic degradation products that can be readily absorbed or excreted, include appropriate permeability and processability for designed application, possess a degradation time coinciding with their function.
B) polymethyl methacrylate is one of the earliest polymers used for rigid gas permeable lenses. It’s structurally similar to lucite and plexiglas. Polymacon which has 38% of water in composition is typical of the polymers used for soft lenses and it’s a polymer of 2-hydroxyethyl methacrylate. It’s important because it possesses hydrophilic properties.
C) hard contact lenses are made of poly methyl methacrylate which is rigid non gas permeable plastic while soft contact lenses are made of silicone which is flexible and allows oxygen to reach our eyes.