Process of fractionating polymers
AssigneeRohm and Haas Electronic Materials LLC
InventorsLujia Bu, Charles R. Szmanda, Kathleen B. Spear-Alfonso, Kathleen M. O'Connell
Life of this patent
Estimating the term…
Abstract
Provided herein is a process of fractionating ferroelectric, preferably vinylidene fluoride polymers using a solvent having at least one polarizable functional group, and a precipitant. The composition of the fractionated ferroelectric polymers is selected so as to adjust the properties of a ferroelectric film made from the polymers. Films formed using the fractionated vinylidene fluoride polymers have improved properties, particularly with respect to roughness and crystal domain size, and suitability for use in data processing devices.
Claims13
A process of fractionating a vinylidene fluoride polymer, comprising:
- adding a precipitant to a solution comprising a vinylidene fluoride polymer and a solvent, to form a mixture, wherein the solvent has at least one polarizable functional group, wherein the precipitant is miscible with the solvent, and wherein the precipitant is added in an amount sufficient to produce, at a first temperature, a solid-liquid phase separation between the mixture and a fraction of the vinylidene fluoride polymer, based on the molecular weight of the vinylidene fluoride polymer;
- and
- isolating the weight-fractionated vinylidene fluoride polymer from the mixture.
A process of fractionating a ferroelectric polymer, comprising:
- adding a precipitant to a solution comprising a ferroelectric polymer and a solvent, to form a mixture, wherein the solvent has at least one polarizable functional group, wherein the precipitant is miscible with the solvent, and wherein the precipitant is added in an amount sufficient to produce, at a first temperature, a solid-liquid phase separation between the mixture and a fraction of the ferroelectric polymer, based on the molecular weight of the ferroelectric polymer;
- and
- isolating the fractionated ferroelectric polymer from the mixture, wherein the isolated fraction has a narrower molecular weight distribution than the initial ferroelectric polymer dissolved in the solution.
A ferroelectric polymer having a molecular weight distribution ratio of less than 1.3.
Dependencies are inferred from the claim text.