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PAM(polyacrylamids) is a linear polymer. It is one of the most
widely used water soluble polymers. PAM and its derivatives can
be effective flocculator, thickener, paper strengthening agent,
or liquid friction reducer. Its application may cover industries
like water treatment, paper, oil, mine, refinery, textile, construction
etc.
Specification
| |
PAM anionic |
PAM nonionic |
PAM cationic |
PAM amphoteric |
| appearance |
White granulated powder |
| diameter(mm) |
< 2 |
| solid content(%) |
≥88 |
| dissolution(min) |
≤1.5 |
| insoluble(%) |
≤2 |
| molecular weight(K) |
5000-24000 |
3000-6000 |
3000-8000 |
8000-15000 |
hydrolysis
(%) |
13-30 |
5-15 |
5-50 |
10-20 |
Molecular weight can vary in the range indicated above upon client's
request.
Physical property & Characteristics of PAM ¡¡¡¡
1. physical property£º(CH2CHCONH2)r
PAM is a linear polymer. It is soluble to water, insoluble to common
organic solvents like benzene, ethylbenzene, esters, acetone. PAM
is hygroscopic and the hygroscopicity is correlative to its ionization.
The aqueous solution of PAM is an almost transparent thick liquid
which is nontoxic and noncorrosive. PAM is stable to heat up to
100°C. Above 150°C, it decomposes to nitrogen and transmolecular
iminization accures, which render it insoluble to water. The density
of PAM is 23°C 1.302 g/ml, and its vitrification temperature
is 153°C. PAM shows non-newton fluid features under stress.
2. characteristics
- flocculation£ºsuspending particles can
be flocculated by PAM via charge-patch neutralization or bridging
mechanism.
- adhesive ability
- friction reduction£ºTrace amount of PAM in water can effectively
reduce 50-80% of frictions.
- Thickening£ºPAM possesses thickening ability at acid or neutral
condition. At PH>10, hydrolysis accures, rendering half network
structure which enhances the thickening effect.
3¡¢mechanism£º
- flocculation£ºWhen PAM is used to effect
flocculation, certain factors should be concerned: electrokinetic
potential on the surface of granules, viscosity, turbidity and
PH. The electrokinetic potential makes granules repulsive to each
other. PAM neutralizes the charges on the surface of the granules
and help flocculation.
- bridging effect£ºGranules can be attached by PAM which takes
effect like bridges. The granules finally go towards aggregates.
- surface absorption£ºPolar functional groups in PAM can effect
surface absorption.
- supporting effect:PAM moleculars connect the dispersed phases
via mechanical, physical and chemical forces, thus forming network
structure to support the phases.
Usage£º¡¡¡¡
- PAM has a high molecular weight and good water solubility. It
can import different ionic groups to achieve different properties.
Low molecular- weight PAM is good dispersant, thickener or stabilizer;
high molecular- weight PAM is good focculator.
- It can be used to make hydrophilic or hydrophobic gels, which
possess good adhesive ability.
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Polyacrylamide
