Environmental Engineering Reference
In-Depth Information
Table 3.2
Structure of Common Addition Polymers and their
Applications
Polymer
Repeat unit
Applications
Low-density polyethylene
(LDPE)
-CH
2
-CH
2
-
Plastic film and
bags
High-density
polyethylene (HDPE)
-CH
2
-CH
2
-
Bottles, milk jugs,
toys
Polypropylene (PP)
-CH(CH
3
)-CH
2
-
Caps, tape, film,
fiber
Poly(vinyl chloride)
(PVC)
-CH(Cl)-CH
2
-
Siding, pipes,
flooring
Polystyrene (PS)
-CH(C
6
H5)-CH
2
-
Foam cups, cutlery
Poly(tetrafluoroethylene)
(PTFE)
-CF
2
-CF
2
-
Nonstick surfaces
Poly(vinylidene chloride)
(PVDC)
-CH
2
-CCl
2
-
Saran wrap
Polyacrylonitrile (PAN)
-CH
2
-CH(CN)-
Textile fibers
Poly(methylmethacrylate)
(PMMA)
-CH
2
-C(CH
3
)(COOCH
3
) Glazing in skylights,
windows, and
picture frames.
Used also in lighting
fixtures
Poly(vinyl acetate)
(PVAc)
-CH
2
-CH(COOCH
3
)
Chewing gum and
bubble gum base,
adhesives
The sequence of reactions is illustrated below in the polymerization of
ethylene:
Initiation
of reaction by free radical formation
Propagation
of radical chain
