Starch and carboxylic acid binder compositions and articles made therewith

A fiber-containing composite comprising:

• woven or non-woven fibers;
• and
• a binder that holds the fibers together, wherein the binder is formed by curing a binder composition comprising:
• 20 wt. % to 80 wt. % starch having a weight average molecular weight that ranges from 1×106 Daltons to 1×107 Daltons,
• 20 wt. % to 80 wt. % polycarboxylic acid,
• 1 wt. % to 10 wt. % cure catalyst, and
• water,
• wherein the water content of the binder composition is determined by:
• measuring a moisture content of the fibers coated with the binder composition;
• comparing the moisture content of the coated fibers to a preset moisture value for the fibers coated with the binder composition;
• and
• adjusting the water content of the binder composition when the moisture content of the coated fibers differs by more than an accepted deviation from the preset moisture value.

A method of making a fiber-containing composite, the method comprising:

• applying a binder composition to fibers to form coated fibers, wherein the binder composition comprises:
• a starch having a weight average molecular weight that ranges from 1×106 Daltons to 1×107 Daltons, and
• a polycarboxylic acid,
• measuring a moisture content of the coated fibers, wherein if the moisture content of the coated fibers differs by more than an accepted deviation from a preset moisture value, then the moisture content is adjusted to be closer to the preset moisture value;
• and
• curing the coated fibers in a curing oven to form the fiber-containing composite.