Utilizing aTREF data with chemometric analysis for determining the types of polyethylene present in polymer blends and multilayer films

A method of producing a polymer resin comprising:

• (a) providing a polymer sample of the polymer resin, wherein the polymer sample comprises two or more polymer components;
• (b) subjecting at least a portion of the polymer sample to analytical temperature rising elution fractionation (aTREF) analysis to yield an aTREF elution trace;
• (c) identifying the two or more polymer components of the polymer sample to yield two or more identified polymer components;
• wherein the identifying comprises comparing the aTREF elution trace with an identification library that comprises a plurality of known polymer aTREF elution traces, wherein each of the plurality of known polymer aTREF elution traces is correlated with a known polymer component, wherein the known polymer component is characterized by an identifying parameter, and wherein the identifying parameter is selected from the group consisting of density, short chain branching, crystallization temperature, melt index, high load melt index, molecular weight distribution, and combinations thereof;
• (d) quantifying an amount of each of the two or more identified polymer components in the polymer sample to yield two or more quantified polymer components, wherein the quantifying comprises chemometric analysis of the aTREF elution trace;
• and
• (e) producing the polymer resin by:
• (i) responsive to step (c), selecting one or more monomers that can form the two or more identified polymer components;
• and polymerizing the one or more monomers to produce the polymer resin;
• wherein the polymerizing occurs under a plurality of polymerization conditions;
• and wherein each polymerization condition of the plurality of polymerization conditions is selected responsive to step (d) from the group consisting of monomer concentration, comonomer concentration, hydrogen to monomer ratio, temperature, catalyst concentration, cocatalyst concentration, pressure, residence time, reactor solids concentration, and combinations thereof;
• (ii) responsive to step (c), selecting the two or more polymer components;
• and responsive to step (d), blending the two or more polymer components to produce the polymer resin;
• or
• (iii) both (i) and (ii).

A system for analyzing a polyethylene resin comprising:

• an analytical instrument comprising an analytical temperature rising elution fractionation (aTREF) column and an infrared (IR) detector;
• wherein the aTREF column is configured to receive a polyethylene sample solution, wherein the polyethylene sample solution comprises a polyethylene sample of the polyethylene resin and an aTREF solvent, wherein the polyethylene sample comprises two or more polyethylene components;
• wherein the aTREF column is configured to elute the two or more polyethylene components at different elution rates along the aTREF column to produce an aTREF eluent;
• and wherein the IR detector is configured to detect the two or more polyethylene components in the aTREF eluent and yield an aTREF elution trace;
• and
• a computer system configured to receive the aTREF elution trace from the analytical instrument, wherein the computer system comprises at least one processor;
• wherein the at least one processor compares the aTREF elution trace with an identification library and identifies the two or more polyethylene components of the polyethylene sample to yield two or more identified polyethylene components;
• wherein the identification library comprises a plurality of known polyethylene aTREF elution traces, wherein each of the plurality of known polyethylene aTREF elution traces is correlated with a known polyethylene component, wherein the known polyethylene component is characterized by an identifying parameter, and wherein the identifying parameter is selected from the group consisting of density, short chain branching, crystallization temperature, melt index, high load melt index, molecular weight distribution, and combinations thereof;
• and wherein the at least one processor performs chemometric analysis of the aTREF elution trace to quantify an amount of each of the two or more identified polyethylene components in the polyethylene sample to yield two or more quantified polyethylene components.