What features of cellulose molecules account for both the strength and the water absorbing qualities of paper?
What features of cellulose molecules account for both the strength and the water absorbing qualities of paper towels?
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- A cellulose molecule consists of 2 glucose anhydride units. This unit is called a cellobiose unit. On the surface of this molecule are hydrogen and hydroxy units which are free to form hydrogen bonds with water, imparting absorbency, and the ability to cross link with other cellobiose units, which gives strength. The molecule is a monomer - it links with other cellobiose units to form a polymer - a long straight chain of cellobiose units. The number of cellobiose units linking together is called the degree of polymerization (dP) In wood, this dP is anywhere from a few hundred to about 2500. In cotton, the dP is about 10,000. These chains coordinate with other polymers via hydrogen bonding to form fibers. The length of the these fibers give cellulose it's strength. Conifers (softwoods like pine) have the largest dP's of wood. Hardwoods (maples, oaks) have shorter dP's making a smaller cellulose unit that allows the paper to form better. (the smaller units are able to conform well with the larger units) Papermakers use recipes that mix these to combine the strength of long dP's with the formation abilities of shorter dP's to dictate the properties of the paper they wish to make; smooth surface for printing, absorbency, etc
- oook... that guys aanswer was wayy too complicated for me i just did this in gr 12 bio so... basically.. cellulose has a certain type of linkage (i forget which ight now) that allows it to be straight chained rather than kinked or coiled if sojmethign is straight chained klike that.. the strands sit coser togetehr making it strong and this is why it can absorb and hold water pretty well too sorry about the retarded typos
- The animal kingdom is made up of proteins and the vegetable kingdom is made up on cellulose. The cellulose in wood are processed in different ways, chemically, to produce a variety of substances like boxes, papers, paper towel, toilet paper etc.
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