β-crystalline polypropylenes
View Patent ↗Disclosed herein are p-urea phenyl derivatives of the formula: wherein R 1 and R 2 are independently selected hydrocarbyl groups. These derivatives are useful as haze reducing agents in propylene polymers and copolymers.
1. A composition comprising:
(A) a crystallizable propylene polymer, and
(B) about 0.15% to about 1%, relative to the weight of component (A), of a p-urea phenyl derivative of the formula:
wherein R 1 and R 2 are cyclopentyl.
2. The composition of claim 1 further comprising about 0.001 to about 5%, relative to the weight of component (A), of at least one additional nucleating agent selected from the group consisting of:
(1) Aromatic sorbitol acetals;
(2) Nucleating agents based upon salts of phosphoric acid;
(3) Nucleating agents based upon salts of carboxylic acids;
(4) Nucleating agents based upon carboxy aluminum-hydroxide;
(5) Nucleating agents based upon salts of rosin/adiebetic acid;
(6) Zinc (II) monoglycerolate;
(7) Nucleating agents based upon diamide compounds; and
(8) Nucleating agents based upon trimesic acid derivatives.
3. A method for reducing haze in crystallizable propylene polymers comprising adding to said polymer about 0.15% to about 1%, relative to the weight of the polymer, of a urea phenyl derivative of the formula:
wherein R 1 and R 2 are cyclopentyl.
4. The method of claim 3 further comprising the step of adding about 0.001 to about 5%, relative to the weight of the polymer, of at least one additional nucleating agent selected from the group consisting of:
(1) Aromatic sorbitol acetals;
(2) Nucleating agents based upon salts of phosphoric acid;
(3) Nucleating agents based upon salts of carboxylic acids;
(4) Nucleating agents based upon carboxy aluminum-hydroxide;
(5) Nucleating agents based upon salts of rosin/adiebetic acid;
(6) Zinc (II) monoglycerolate;
(7) Nucleating agents based upon diamide compounds; and
(8) Nucleating agents based upon trimesic acid derivatives.
5. A composition of matter comprising from about 0.15% to about 1% of a p-urea phenyl derivative of the formula:
wherein R 1 and R 2 are cyclopentyl.