The paper industry is one of the most water-in-tensive industriesand a major consumer of water-soluble polymers. The use ofpolymers can increase the productivity of paper machines. improve paper quality, reduce water consumption, and reducethe harmful effects of paper on the environment.

Polymers have many applications in Papermaking, mainly:
1. Retention: Add polymer to the machine head to make the filler(titanium dioxide, kaolin, calcium carbonate,etc.)and fiber morein the paper.
The ionic nature of the polymer depends on thenature of the process.
2. Filtration: Adding polymer in the wet part of the paper machineto increase the filtration speed to increase the speed of the drying operation, there by increasing the output of the paper-machine.
3. Recover paper fibers with medium and high cationicpolymers.
4. Improve the dry strength of paper with low cationicity and lowmolecular weight polymers.
5. Temporarily increase the wet strength with the polymer in the wet end of the paper machine.
6. Treat the paper mill process water, wastewater and sludgewith polymer.
7. De-inking with recycled coaqulant followed by high molecularweight flocculant for waste paper regeneration.