Objective
Until recently, starch has been used extensively in paper industry, for different uses, mainly in its native form. As a result of the demand for higher paper properties, and of the increase of paper machine speeds, synthetic polymers are often used instead of starch, due to their higher performances, even though they are more expensive.
The aim of the present project is to increase starch consumption in the paper industry, through the development of new efficient derivatives, obtained by chemical and biological modifications. Thanks to genetic engineering, more well-defined and adapted starch products are already becoming available, and should continue to develop as a result of the present project.
Starch in paper-machine wet-end : New modified starches with a higher degree of cationization are now produced. This should give much better possibilities to develop retention aid systems based on starch. The higher charge on starch also makes possible its use in contaminated papermaking systems.
Starch with a high degree of hydroxyl groups, is a good agent for promoting bonding. Chemically and biologically modified starches could certainly lead to new dry and wet strength agents.
Starch for coating : by controlling the covering ability of the coating color and the paper optical properties, while minimizing the negative effect of viscosity, starch could replace a significant part of latex and other synthetic polymers. This could be obtained through the control of pigment aggregation induced by modified starches.
Starch as filler : the use of starches as fillers requires a modification for controlling its swelling in water. Completely insolubilized starches can be used in order to improve opacity. Partly swollen starches are able to bond with fibre surfaces, thus improving paper strength. For a good retention, the chemical cross-link may also be coupled to an adjustment of electric charges.
Each subject will contain three phases : definition of new derivatives, laboratory screening, trials on high speed pilots and semi-industrial machines. Two starch producers and a papermaker are involved in the project.
Funding Scheme
CSC - Cost-sharing contracts
Coordinator
38020 Grenoble
France
Participants (5)
2151 Espoo
Muenchen
24570 Le Lardin-saint-lazare
29191 Kristianstad
11486 Stockholm
