Method to decrease the acetaldehyde and formaldehyde content in the cellulosic fiber-reinforced polypropylene composites thermoplastics

A method of reducing aldehyde emissions during injection molding of a part with a cellulosic fiber-reinforced polypropylene composition comprising the steps of:

• providing pelletized cellulosic fiber-reinforced polypropylene composition material;
• providing an aldehyde reducing composition, said aldehyde reducing composition comprising at least two moieties selected from the group consisting of anthranilamide, anthranilamide derivative, 1,8 diaminonaphthalene, 3,4-diaminobenzoic acid and combinations thereof;
• providing an injection molding machine capable of the predetermined parameters necessary for injection molding of the cellulosic fiber-reinforced polypropylene composition, said injection molding machine including a hopper portion for holding the pelletized cellulosic fiber-reinforced polypropylene composition material, a feed throat portion, a mixing chamber installed between the hopper and feed throat portions, and a pump for delivering an effective amount of the aldehyde reducing composition to the mixing chamber;
• metering an effective amount of the aldehyde reducing composition into the mixing chamber containing a predetermined amount of the pelletized cellulosic fiber-reinforced polypropylene composition;
• operably mixing the pelletized cellulosic fiber-reinforced polypropylene composition with the aldehyde reducing composition for wetting the surface of the pellets with the aldehyde reducing composition;
• and
• injection molding of the part with the wetted pelletized mixture.

A method of reducing aldehyde emissions during injection molding of a part with a cellulosic fiber-reinforced polypropylene composition comprising the steps of:

• providing pelletized cellulosic fiber-reinforced polypropylene composition material;
• providing an aldehyde reducing composition, said aldehyde reducing composition comprising at least two moieties selected from the group consisting of anthranilamide, anthranilamide derivative, 1,8 diaminonaphthalene, 3,4-diaminobenzoic acid and combinations thereof;
• providing an injection molding machine capable of the predetermined parameters necessary for injection molding of the cellulosic fiber-reinforced polypropylene composition, said injection molding machine including a barrel for injection molding, a hopper portion for holding the pelletized cellulosic fiber-reinforced polypropylene composition material, a feed throat portion, a mixing chamber installed between the hopper and feed throat portions, and a peristaltic pump for delivering an effective amount of the aldehyde reducing composition to the mixing chamber;
• metering the effective amount of the aldehyde reducing composition into the mixing chamber containing a predetermined amount of the pelletized cellulosic fiber-reinforced polypropylene composition during a recovery time of the injection molding cycle;
• operably mixing the pelletized cellulosic fiber-reinforced polypropylene composition with the aldehyde reducing composition for wetting the surface of the pellets with the aldehyde reducing composition;
• and
• injection molding of the part with the wetted pelletized mixture;
• wherein at least acetaldehyde and formaldehyde emissions are reduced to predetermined levels meeting requirements.