Poly(Dimethyl diallyl ammonium Chloride), Other name: Polydadmac, PDMDAAC, PDADMAC; Polydadmac is a strong cationic polyelectrolyte with a colorless to yellowish viscous liquid. It is safe, non-toxic, soluble in water, non flammable, strong cohesion, good hydrolysis stability, no gel, insensitive to changes in pH value, and has chlorine resistance. The freezing point is about - 2.8 ℃, the specific gravity is about 1.04g/cm, and the decomposition temperature is 280-300 ℃. In view of the above advantages, polydadmac has been widely used as cationic coagulant in wastewater treatment, mining and mineral processing, aldehyde free fixing agent in textile industry, anionic garbage catching agent and AKD curing accelerator in papermaking process, clay stabilizer for drilling and cationic modifier for acid fracturing in water injection in oilfield industry. In addition, it is also used as conditioner, antistatic agent, humidifier, shampoo and moisturizer for skin care.
With the development of polydadmac's application range, the research and development of new polydadmac products with high relative molecular weight, series of relative molecular weight and controllable relative molecular weight distribution through preparation process research is the direction of polydadmac product research and development. On the basis of ensuring that the number of impurities in monomer is small and its mass fraction is low, and the monomer conversion rate in the product is high, the work can be carried out from the following aspects:
Control of relative molecular weight distribution
Based on the preparation of polydadmac with high relative molecular weight, the research on the series of products with relative molecular weight has made preliminary progress. Further study on the regulation of the distribution of relative molecular weight can provide the products with certain relative molecular weight with concentrated distribution, which can lay a foundation for the development and improvement of the properties of the series products.
Development of dry powder products
At present, colloidal and liquid products have the disadvantage of inconvenient transportation, and the dry powder products have the problem of low relative molecular weight. Therefore, based on the existing high molecular weight polydadmac products, the drying and milling process is studied, so as to obtain the powder products with higher molecular weight, which provides convenience for the packaging, transportation and use of polydadmac, and is more conducive to the production Expand the application of the product.
Microstructure control and adjustment of polymers
Micro crosslinked polymers have many properties such as strong water absorption, many branched chains and stable structure, which may have unique properties in the application process. Based on the characteristics of unit structure distribution on the linear long chain of polydadmac, the process conditions can be appropriately changed to promote the formation of branched chain or micro crosslinked products without adding crosslinking agent and other monomers; micro crosslinking products can also be produced by properly adding micro crosslinking agent, which is conducive to enrich the types of polyydmac polymer and develop its new application properties.