Use this reference to compare specification fields across anionic, cationic and nonionic dry PAM, read a supplier TDS and prepare a purchase brief. It is a parameter lookup; product availability, batch acceptance and quotation remain grade-specific.
Tables 1–2 show example purchase windows and screening candidates, not universal limits or ChinaPAM model specifications. Use the quoted grade TDS and batch COA for binding values. Charge examples below use a declared molar basis; other percentages are by mass of supplied product. Do not substitute mol%, wt% or meq/g for one another.
| Parameter | Anionic PAM (APAM): example | Cationic PAM (CPAM): example | Nonionic PAM (NPAM): example | Method / conditions to confirm |
|---|---|---|---|---|
| Appearance | White granular powder | White to off-white granular powder | White granular powder | Visual |
| Charge type | Negative (carboxylate) | Positive (cationic groups; exact chemistry is grade-specific) | Nonionic; verify any residual hydrolysis stated for the grade | — |
| Charge density / hydrolysis (declared molar basis) | 5 – 40% | 5 – 80% | 0 – 5% | Specify mol% of charged repeat units and the supplier method; hydrolysis is reported only where applicable. A measured meq/g value needs its own mass basis and conversion. |
| Molecular weight | 6 – 28 million Da | 6 – 20 million Da | 8 – 15 million Da | Identify the MW average and method. For viscosity-based MW, state polymer, solvent, salt concentration, temperature and the applicable correlation. |
| Solid content | Illustrative minimum: ≥88% or ≥90%; select one agreed limit | Illustrative minimum: ≥88% or ≥90%; select one agreed limit | Illustrative minimum: ≥88% or ≥90%; select one agreed limit | Declared solids/moisture method; 105 °C is an example only if that method uses it |
| Residual acrylamide | Example purchase limits: ≤0.05%, or ≤0.025% where specifically agreed for the intended use | Example purchase limits: ≤0.05%, or ≤0.025% where specifically agreed for the intended use | Example purchase limit: ≤0.05% | State residual acrylamide as mass fraction of supplied product and the validated method; match the grade and intended use. |
| Example dissolution-test window (0.1% product, 20–40 °C) | 30 – 90 min by MW | 45 – 90 min | 60 – 90 min | Stated concentration, water quality, temperature and mixing conditions |
| Water insolubles | ≤ 0.3% | ≤ 0.3% | ≤ 0.5% | Define solution concentration, filter medium, drying basis and result denominator. |
| Bulk density | 0.60 – 0.85 g/cm³ | 0.60 – 0.85 g/cm³ | 0.60 – 0.85 g/cm³ | Specify loose bulk density and its method; tapped density is a separate result. EN 1407 gives 0.5–0.9 g/cm³ as typical only for the anionic/nonionic products in its scope [3]. |
| Particle size | ≥ 90% between 0.2 – 1.6 mm | ≥ 90% between 0.2 – 1.6 mm | ≥ 90% between 0.2 – 1.6 mm | Define sieve apertures, retained mass basis and sample condition. |
| pH (0.1% solution) | 6 – 8 | 3 – 6 | 6 – 8 | Measure at the stated product concentration, water composition and temperature. |
| Example application-test pH envelope | 4 – 12 | 1 – 10 | 1 – 10 | Qualify at the actual process pH; test the intended endpoints and polymer stability. |
| Shelf life / storage conditions | 24 months in the manufacturer dry-polymer example [1]; grade storage conditions control | 24 months in the manufacturer dry-polymer example [1]; grade storage conditions control | 24 months in the manufacturer dry-polymer example [1]; grade storage conditions control | Keep sealed and dry. Below 35 °C is an illustrative storage limit; the grade TDS must confirm the conditions for its stated shelf life. |
A manufacturer example shows why conditions matter: MT Aqua Polymer lists 13 million Da for nonionic N-100S and 16 million Da for anionic A-110L. Both list a bulk-specific-gravity reference value of 0.65 ± 0.10. Their 0.1% solution-pH references are 5–7 and 6–8 respectively. The list separately states 0.1% solution viscosity at 25 °C and identifies the physical-property figures as reference values [5]. These are that manufacturer’s reference values, not ChinaPAM grade specifications.
| Ionic type | Charge / hydrolysis example (mol%) | Molecular weight | Application to investigate; confirm by test |
|---|---|---|---|
| Anionic | 5 – 15% (low) | 15 – 20 M (high) | Sand washing, aggregate wash water, stone-cutting slurry |
| Anionic | 15 – 30% (medium) | 15 – 20 M | Mineral tailings thickening, coal preparation, municipal primary clarification |
| Anionic | 25 – 40% (high) | 6 – 15 M | Industrial effluent after hydroxide precipitation |
| Anionic | 20 – 30% | 25 – 28 M (ultra-high) | Fine tailings, TBM and bentonite slurry, red mud |
| Anionic (PHPA / HPAM) | 25 – 35% | 15 – 25 M | Drilling fluid encapsulation and viscosity, EOR polymer flooding |
| Cationic | 5 – 20% (lower-charge example) | 8 – 12 M | Paper retention and drainage, low-organic sludge |
| Cationic | 20 – 40% (mid-charge example) | 8 – 12 M | Municipal mixed sludge on belt presses and filter presses |
| Cationic | 40 – 60% (higher-charge example) | 10 – 12 M | Waste activated sludge, food and paper mill sludge |
| Cationic | 60 – 80% (high to very high) | 11 – 14 M | Digested sludge, oily and fat-rich sludge, centrifuges and screw presses |
| Nonionic | < 5% | 8 – 15 M | Acidic mine water, low-pH tailings, high-salinity water |
How to read a polyacrylamide specification sheet
Start with ionic type, charge or hydrolysis basis, molecular weight or intrinsic viscosity, solids or active-polymer content, and residual monomer. These fields help shortlist candidates, but application tests determine whether a grade meets the process target. Read MW together with charge, polymer structure, preparation and the solids-separation equipment.
Solids and active-polymer content are different quantities unless the product documentation establishes otherwise. If 90% and 80% are both confirmed active-polymer mass fractions, 0.90 ÷ 0.80 − 1 = 12.5% more active polymer per kilogram of product. This calculation cannot be inferred from solids content alone. Residual-monomer requirements depend on the actual grade, destination, use and dose.
For U.S. public drinking-water systems, 40 CFR 141.111 controls the combination of residual monomer and polymer dose: 0.05% residual acrylamide dosed at 1 ppm, or an equivalent combination [4]. This is not a stand-alone food-use limit. Check the exact product approval and maximum use level for the intended project.
Molecular weight vs. intrinsic viscosity
Suppliers may infer molecular weight from intrinsic viscosity using a stated Mark–Houwink relationship. The polymer, solvent, temperature and constants must match the measurement [2]. Ask for the reported method and conditions before comparing two quoted MW figures; do not assume one universal 1 mol/L NaCl at 30 °C conversion for every PAM grade.
Writing a purchase specification
Name the ionic type and the required charge window with its basis, the MW or viscosity requirement with its method, and the agreed solids/active content, residual monomer, dissolution and insolubles requirements. A purchase window such as cationic 40 ± 5%, solids ≥89% and insolubles ≤0.3% is an illustrative brief, not a specification for all PAM. Lock the actual values with the selected grade and test protocol.
- Ionic type and charge window, with the charge basis
- MW or intrinsic-viscosity requirement, method and conditions
- Solids or active polymer, residual monomer, insolubles and dissolution acceptance requirements
- Packaging, for example 25 kg bags or bulk bags as quoted, plus shelf life and documented storage conditions
- Grade TDS, batch COA, SDS and any use-specific approval documents
Use the RFQ specification template for the complete process, acceptance and commercial brief, and the COA, TDS and SDS review for document and batch checks. For process-duty screening, use the flocculant selection chart.
Anionic Brand Equivalents by Charge and Molecular Weight
The tables above show illustrative specification and purchase-review windows. If you are matching a named anionic grade, the pages below explain how we screen an equivalent for each one. Ask us to review the required grade identity, application and documentation before quotation.
Very low charge
- FLOPAM AN 905 SH equivalent — very low charge, very high molecular weight
Low charge
- FLOPAM AN 913 equivalent — low charge, standard molecular weight
- FLOPAM AN 913 SH equivalent — low charge, very high molecular weight
AN 900 series
- FLOPAM AN 900 HD equivalent — anionic PAM, HD grade
- FLOPAM AN 900 SHD equivalent — anionic PAM, SHD grade screening
High charge
- FLOPAM AN 945 SH equivalent — high charge, very high molecular weight
- FLOPAM AN 956 equivalent — high charge, standard molecular weight
- FLOPAM AN 956 SH equivalent — high charge, very high molecular weight
- FLOPAM AN 970 VLM equivalent — high charge, very low molecular weight
Not sure which grade you need? Send us your current product name and application and we will suggest a screening route.
Frequently Asked Questions
What is the standard solid content of polyacrylamide powder?
The table illustrates alternative powder-solids minimum requirements of 88% or 90%; the buyer must choose the actual grade limit. Manufacturer reference [1] describes about 90% active dry polymer and 25–50% active emulsion in its stated context. Confirm whether a supplier’s figure is solids or active polymer and whether it is a minimum, range or typical value.
What residual acrylamide level is acceptable?
Agree the limit for the actual grade, destination and intended use. The ≤0.05% and ≤0.025% figures shown are illustrative purchase-review limits; they do not establish regulatory permission, food-contact suitability or a certification claim.
Does higher molecular weight always mean better flocculation?
No. Higher MW can increase bridging within a comparable polymer system, but dissolution and shear response also depend on the grade and preparation. Compare charge, structure, feed chemistry and equipment in a defined application test rather than choosing the highest MW alone.
Related
- /products/polyacrylamide
- /products/anionic-polyacrylamide
- /products/cationic-polyacrylamide
- /products/nonionic-polyacrylamide
- /blog/polyacrylamide-molecular-weight-guide
- /blog/polyacrylamide-charge-density-explained
- /blog/polyacrylamide-coa-tds-sds-review
- /blog/polyacrylamide-rfq-specification-template
- /blog/pam-vs-pac-vs-alum-vs-ferric-comparison
- /blog/flocculant-selection-chart-by-wastewater-type
- /blog/polyacrylamide-physical-chemical-properties
[1] Kemira Water Handbook (2020), stated polymer examples · [2] Malvern Panalytical, Mark–Houwink conditions
[3] EN 1407:2023 public preview, scope and physical properties · [4] 40 CFR 141.111, acrylamide dose/monomer treatment technique
Data note: numeric purchase windows and trial combinations are author-selected examples, not a ChinaPAM model TDS or guaranteed application result. The cited manufacturer and standard references support the stated concepts and scoped examples. Grade TDS, batch COA and SDS are available on request.
[5] MT Aqua Polymer, powder-product reference list and test conditions