Polymers and Plastics

The glass transition temperature (Tg) is the temperature at which a polymer transitions from a rubbery state to a glassy state. Below Tg, the polymer becomes brittle and glassy, while above Tg, it becomes soft and rubbery.

Tensile testing is a mechanical test used to determine the tensile strength and elongation at break of a polymer. It involves applying a tensile force to a specimen until it breaks and measuring the force and elongation at the point of failure.

Differential scanning calorimetry (DSC) is a thermal analysis technique used to determine the melting point, glass transition temperature, and other thermal transitions in a polymer. It involves measuring the heat flow into or out of a sample as it is heated or cooled at a controlled rate.

Fourier transform infrared (FTIR) spectroscopy is a technique that measures the absorption of infrared radiation by a polymer. The absorption spectrum provides information about the chemical structure and functional groups present in the polymer.

Impact testing is a mechanical test used to evaluate the impact resistance of a polymer. It involves subjecting a specimen to a sudden impact force and measuring the energy absorbed or the damage caused by the impact.

X-ray diffraction (XRD) is a technique commonly used to determine the crystallinity of a polymer. It involves irradiating a sample with X-rays and analyzing the diffraction pattern to obtain information about the crystal structure and degree of crystallinity.

Nuclear magnetic resonance (NMR) spectroscopy is a technique that measures the absorption of nuclear magnetic resonance radiation by a polymer. The NMR spectrum provides information about the chemical structure, molecular weight, and dynamics of the polymer.

Flexural testing is a mechanical test used to evaluate the flexural strength and modulus of a polymer. It involves applying a load to a specimen supported at two points and measuring the deflection and load at the point of failure.

Scanning electron microscopy (SEM) is a technique commonly used to determine the surface morphology of a polymer. It involves scanning the surface of a sample with a focused beam of electrons and collecting the secondary electrons emitted from the surface. SEM provides high-resolution images that allow for the visualization of surface features and topography.

Ethylene vinyl alcohol (EVOH) is a high-barrier packaging material that provides excellent protection against moisture and oxygen transmission, making it suitable for packaging products that require a long shelf life.

Water-based mounting media are often used for temporary preparations due to their ease of use and removal, allowing for quick observation and subsequent processing of the specimen.

Canada balsam is commonly used for permanent preparations due to its durability and resistance to fading over time, ensuring the longevity of the mounted specimen.

Rubber is a flexible and durable material that provides good traction and cushioning.

Polyethylene Terephthalate (PET) is a polyester, not a petroleum-based plastic.

Poly(lactic acid) (PLA), poly(glycolic acid) (PGA), and poly(lactic-co-glycolic acid) (PLGA) are all biodegradable polymers commonly used in drug delivery systems. They are biocompatible and can be tailored to control drug release rates and target specific tissues.