The molecular weight of polyacrylic acid and its sodium salt is about 2000, which is better for scale inhibition.

When the molecular weight is higher, 3000-6000. The scale inhibition effect decreases and the dispersion effect begin to rise.

Polycarboxylic Antiscalant and Dispersant

Polyacrylic Acid (PAA)	IR-1010 General Purpose Acrylic Homopolymer Scale Inhibitor
Polyacrylic Acid Sodium (PAAS)	IR-1100 General Purpose Acrylic Homopolymer Scale Inhibitor
Hydrolyzed Polymaleic Anhydride (HPMA)	IR-2000 Carboxylate-sulfonate Copolymer Dispersant
Acrylic Acid Maleic Acid Copolymer (MA/AA)	IR-2100 Carboxylate-sulfonate Copolymer Dispersant
AA AMPS Copolymer	IR-3100 Carboxylate-sulfonate Nonionic Terpolymer
AA/HPA, Acrylic Acid-hydroxypropyl Acrylate Copolymer	IR-5000 Carboxylate-sulfonate Copolymer Dispersant
IR-241 Acrylic Acid/Acrylate/Phosphonic Acid/Sulfosalt Tetra Copolymer	IR-904 Aqueous Dispersing Agent
IR-613 Acrylic Acid/Acrylate/Sulfosalt Terpolymer	IR-928 Polycarboxylic Acid Concrete Superplasticizer
Phosphinocarboxylic Acid Copolymer (PCA POCA)	Polyepoxysuccinic Acid (Sodium Salt), PESA
IR-1000 General Purpose Acrylic Homopolymer Scale Inhibitor	Polyaspartic Acid (Sodium Salt), PASP