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The Chemistry and Technology of Petroleum
TABLE 6.3
Polymer Degradation in Service
Type of Degradation
Susceptibility
Cause
Remarks
Polyacrylamide
Xanthan Gum
Chemical
High
Moderate
The cations Na +
, Ca 2+
, Mg 2+
Divalent ions are more detrimental
Chemical
High
High
Transition metal ions
Aggravated by high temperatures and high pH
Chemical
High
High
Oxygen and oxidizing agents
Aggravated by high temperatures
Chemical
High
High
Hydrolysis by acidic or basic chemicals
Aggravated under aerobic conditions or high
temperatures
Thermal
High (>250°F)
High (>160°F)
High temperature
Aggravated under aerobic conditions or high pH
Microbial
Moderate
High
Yeasts, bacteria, fungi
Aggravates by warm temperatures and/or under
aerobic conditions
Mechanical shear
High
Low
Intense shear stress and high flux such as
that occurring with flow through valves,
orifices, and low-permeability formations
Aggravated by di- and trivalent cations