CHM Unit 8 Polymers
plasticizers
-PVC commonly conatins plasticizers -disrupt the regular packing of polymer molecules
hdpe
-exhibits a highly ordered molecular structure -has a slightly higher density, -greater rigidity, -more strength - higher melting point than LDPE.
different forms of polystyrene
-expandable -crystal
hdpe
-high-density polyethylene plastic; -commonly used for milk containers and soft drink bottles -linear chain -egg cartons/foam
addition
5 of the big 6 undergo ____ polymerization
natural; amino acids
A protein is a ____ polymer made up of monomers called ____
endocrine disruptors
Chemicals that disrupt normal hormone functions
natural
DNA is a ____ polymer
electrons
Dispersion forces arise in a polymer because each atom in the long polymeric chain contains _____
t
In vinyl chloride, one of the H atoms of ethylene is replaced by a Cl atom. Similarly, in propylene, one of the H atoms of ethylene is replaced by a methyl group (-CH3).
phenyl
The _____ group consists of six carbon atoms arranged to form a hexagon:
intermolecular
These ________ forces differ from the covalent bonds that exist within molecules arising from shared pairs of electrons
polymer
a chemical compound that is in the form of long, repeating chains
condensation polymerization
a process in which the monomers join by releasing (eliminating) a small molecule, usually water.
t
all big 6 are thermoplastic polymers
carboxylic acid; amine
an amino acid contains a ___ and ____
monomers
are the small molecules used to synthesize polymers
monomers
at least 2 or more ____ are required to form a copolymer
shifting baseline
change in what people expect as "normal"
plasticizers
compounds that are added in small amounts to polymers to make them softer and more pliable.
London dispersion forces
describe the attractive forces holding hydrocarbons together, which give rise to their varying boiling points
functional groups
distinctive arrangements of groups of atoms that impart characteristic chemical properties to the molecules that contain them
blowing agent
either a gas or a substance capable of producing a gas to manufacture a foamed plastic.
silicones
inorganic polymers composed of a backbone of alternating Si and O atoms are called ___
ldpe
low-density polyethylene plastic -most commonly used in grocery bags. -food wrap -branched
crude oil
most polymers come from a single raw material: _____ ___
t
not all polymers are plastic. some polymers are natural
plastic in landfills
not readily biodegradable
the big six
polyethylene (low- and high-density), polyvinyl chloride, polystyrene, polypropylene, and polyethylene terephthalate.
plastic
sometimes used as a synonym for synthetic polymer (incorrectly)
dispersion
the intermolecular forces that cause polyethylene to be a solid material are ____ forces
length
the physical properties of a polymer can be drastically altered by changing the ____ of the polymer chain
branching
the properties of LDPE can be changed drastically by modifying the extent and location of ____ on the polyethylene chain
biological
the waste most produced in the US is of _____ origin
source reduction
uses less material and less waste
ethylene
vinyl chloride, propylene, and styrene undergo addition polymerization, just like _____
three monomers closely related to ethylene
vinyl chloride, propylene, and styrene.
thermoplastic polymers
with heat, they can be melted and reshaped over and over again