High temperature continuous viscometry coupled with analytic temperature rising elution fractionation for evaluating crystalline and semi-crystalline polymers

Claim 3

The method of claim 1, wherein step (a) comprises the steps of: (1) adding the solution of polymer sample into a column; and (2) precipitating said solution of polymer sample in said column over said cooling temperature gradient to produce said precipitated polymer sample.

Claim 4

The method of claim 2, wherein step (2) comprises the step of cooling said column in an oil bath to produce said cooling temperature gradient.

Claim 5

The method of claim 2, wherein step (2) comprises the step of cooling said column in an oven to produce said cooling temperature gradient.

Claim 6

The method of claim 1, wherein step (b) comprises the steps of: (1) raising the temperature of a column over said heating temperature gradient; and (2) eluting said precipitated polymer sample from said column to produce said fractionated polymer sample solution.

Claim 7

The method of claim 5, wherein step (2) comprises the step of producing a continuous stream of fractionated polymer sample solution from said precipitated polymer sample.

Claim 8

The method of claim 5, where step (1) comprises heating said column in an oil bath to produce said heating temperature gradient.

Claim 9

The method of claim 5, wherein step (1) comprises heating said column in an oven to produce said heating temperature gradient.

Claim 10

The method of claim 1, wherein said first temperature of step (c) is substantially equal to said second temperature of step (d).

Claim 11

The method of claim 1, wherein the instantaneous concentration of the successive fractions of said fractionated polymer sample solution of step (c) is measured optically.

Claim 12

The method of claim 10, wherein said optical measurement step is performed in the infrared range.

Claim 13

The method of claim 10, wherein said optical measurement step is performed using differential refractometry.

Claim 14

The method of claim 1, wherein the instantaneous specific viscosity of the successive fractions of said fractionated polymer sample solution of step (d) is measured by determining a pressure drop across a capillary tube.

Claim 15

The method of claim 1, further comprising the step (f) of determining the instantaneous viscosity average molecular weight Mv i of the various fractions in accordance with said instantaneous intrinsic viscosity Intv.

Claim 16

The method of claim 1, further comprising the step (f) of determining the instantaneous viscosity average molecular weight in accordance with the following equation: ##EQU30## Where: Mv i =instantaneous viscosity average molecular weight; Intv=instantaneous intrinsic viscosity; K=the intercept in the Mark-Houwink-Sakurada relationship; and a=the exponent in the Mark-Houwink-Sakurada relationship.

Claim 17

The method of claim 15, where step (f) comprises the step of assigning the following values: K=6.23×10.sup.-4 a=0.695.

Claim 18

Apparatus for analyzing a solution of a crystalline or semi-crystalline polymer sample comprising: (a) means for precipitating the polymer sample solution over a cooling temperature gradient to produce a precipitated polymer sample, said precipitated polymer sample being precipitated as a function of its crystallinity or branching configuration or density; (b) means for eluting said precipitated polymer sample over a heating temperature gradient to produce successive fractions of a fractionated polymer sample solution; (c) first means for successively measuring the instantaneous concentration of the successive fractions of said fractionated polymer sample solution, at a first temperature in excess of a precipitation temperature of said fractionated polymer sample solution, to produce instantaneous concentration c data; (d) second means for successively measuring the instantaneous specific viscosity of the successive fractions of said fractionated polymer sample solution, at a temperature in excess of a precipitation temperature of said fractionated polymer sample solution, to produce instantaneous specific viscosity Spv data; and (e) third means for determining the instantaneous intrinsic viscosity Intv of the successive fractions of said fractionated polymer sample solution in accordance with said instantaneous concentration data c from said first means and said instantaneous specific viscosity data Intv from said second means.

Claim 19

Apparatus for analyzing a solution of a crystalline or semi-crystalline polymer sample comprising: (a) means for precipitating the polymer sample solution over a cooling temperature gradient to produce a precipitated polymer sample, said precipitated polymer sample being precipitated as a function of its crystallinity or branching configuration or density; (b) means for eluting said precipitated polymer sample over a heating temperature gradient to produce successive fractions of a fractionated polymer sample solution; (c) first means for successively measuring the instantaneous concentration of the successive fractions of said fractionated polymer sample solution, at a first temperature in excess of a precipitation temperature of said fractionated polymer sample solution, to produce instantaneous concentration c data; (d) second means for successively measuring the instantaneous specific viscosity of the successive fractions of said fractionated polymer sample solution, at a temperature in excess of a precipitation temperature of said fractionated polymer sample solution, to produce instantaneous specific viscosity Spv data; and (e) third means for determining the instantaneous intrinsic viscosity Intv of the successive fractions of said fractionated polymer sample solution in accordance with said instantaneous concentration data c from said first means and said instantaneous specific viscosity data Intv from said second means.

Claim 20

The apparatus of claim 17, further comprising storage means, connected to said first means and said second means, for storing said instantaneous concentration c data and said instantaneous specific viscosity Spv data.

Claim 21

The apparatus of claim 18, further comprising retrieval means, connect to said storage means and said third means, for providing to said third means said instantaneous concentration c data and said instantaneous specific viscosity Spv data stored by said storage means.

Claim 22

The apparatus of claim 18, further comprising means for maintaining said first temperature of said first means and said second temperature of said second means at substantially the same value.

Claim 23

The apparatus of claim 18, wherein said second means comprises a capillary tube and means for determining pressure drop across said capillary tube.

Claim 24

The apparatus of claim 18, wherein said first means comprises optical means.

Claim 25

The apparatus of claim 22, wherein said optical means comprises infrared optical means.

Claim 26

The apparatus of claim 22, wherein said optical mean comprises differential refractometer means.

Claim 27

The apparatus of claim 18, wherein said means for eluting said precipitated polymer sample comprises a column.

Claim 28

The apparatus of claim 17, wherein said means for precipitating comprises oil bath means for producing said cooling temperature gradient.

Claim 29

The apparatus of claim 17, wherein said means for precipitating comprises oven means for producing said cooling temperature gradient.

Claim 30

The apparatus of claim 17, wherein said means for eluting comprises oil bath means for producing said heating temperature gradient.

Claim 31

The apparatus of claim 17, wherein said means for eluting comprises oven means for producing said heating temperature gradient.

Claim 32

The apparatus of claim 17, wherein said third means comprises means for determining said instantaneous intrinsic viscosity Intv in accordance with the equation Intv=Spv/c.

Claim 33

The apparatus of claim 17, further comprising fourth means, connected to said third means, for determining the instantaneous viscosity average molecular weight in accordance with said instantaneous intrinsic viscosity Intv.

Claim 34

The apparatus of claim 17, further comprising fourth means, connected to said third means, for determining the instantaneous viscosity average molecular weight in accordance with the equation ##EQU31## where Mv i is equal to the instantaneous viscosity average molecular weight, K is the intercept of the Mark-Houwink-Sakurada equation, and a is the exponent of the Mark-Houwink-Sakurada equation.