In the pulp and paper industry, many efforts have recently been made to increase the utilization of recycled pulp in pro- ducing paper and paperboard products in order to protect the environment, save energy and lower production cost [12,13]. How- ever, with the increase of the ratio of recycled pulp, the strength and quality of paper and paperboard decreases. Paper strength- ening agents can give the required dry strength to paper and paperboard even when they are made with a large amount of recycled pulp. Drainage and retention are also very important parameters for the deinked pulp in the papermaking process, because they limit the production efficiency of a paper machine [14]. As the paper and paperboard industry continues to increase the speed and output of paper machines, the demands on reten- tion and drainage aids are increasing greatly. Increased water system closure and increased water temperatures are also alter- ing the environment within which the retention and drainage aid has to function, requiring an alternative approach in many cases.