A polyimide precursor solution contains a polyimide precursor, wherein in the case where the polyimide precursor is analyzed by gel permeation chromatography, the elution curve of the polyimide precursor has a region A including a higher-molecular-weight peak and a region B including a lower-molecular-weight peak; a weight average molecular weight determined from the region A in terms of polystyrene is approximately 10,000 or more, and a weight average molecular weight determined from the region B in terms of polystyrene is approximately less than 10,000; and when the area of the region A is a and the area of the region B is b, the polyimide precursor satisfies Equation (1)
a/(a+b)=approximately from 0.70 to 0.98.  Equation 1:

Provided is a guard column including a filling part having a length of 2.0 cm to 3.5 cm formed of a filler, in which the filler is made of porous silica gel having a hydrophilized surface and an average particle size of 1.5 μm to 2.5 μm, and a pressure difference when an aqueous solution is fed at a linear flow rate of 2.1 cm/min is 4.0 MPa or more.

Modified thermoplastic hydrocarbon thermoplastic resins are provided, as well as methods of their manufacture and uses thereof in rubber compositions. The modified thermoplastic resins are modified by decreasing the relative quantity of the dimer, trimer, tetramer, and pentamer oligomers as compared to the corresponding unmodified thermoplastic resin polymers, resulting in a product that exhibits a greater shift in the glass transition temperature of the elastomer(s) used in tire formulations. This translates to better viscoelastic predictors of tire tread performance, such as wet grip and rolling resistance. The modified thermoplastic resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the modified thermoplastic resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, snow performance, and wet braking performance.

A method for detecting a residual crosslinking aid in a crosslinked resin molded body includes a subject heating step in which a crosslinked resin molded body is heated at a temperature of 500° C. or higher and 700° C. or lower for a time of 3 seconds or more and 30 seconds or less, a subject analysis step in which gas chromatographic analysis is performed on a gas generated in the subject heating step, and a detection step in which an unreacted crosslinking aid is detected on the basis of a peak originating from a residual crosslinking aid in a chromatogram obtained in the subject analysis step.

A method for securing qualitative and quantitative information of a high molecular weight additive in a polymer resin sample is disclosed herein. In some embodiments, the method includes separating a fraction of a polymer resin sample using size exclusion chromatography (SEC), wherein the fraction corresponding to a high molecular weight additive, pyrolyzing the fraction in a pyrolysis-gas chromatography/mass spectrometer (Py-GC/MS) to obtain a mass spectrum of the pyrolyzed fraction; identifying a structure of the high molecular weight additive by comparing m/z values for fragment peaks in the mass spectrum to m/z values for fragment peaks in a mass spectrum of a standard, and determining the amount of the high molecular weight additive in the polymer resin sample, relative to the total weight of the polymer resin sample by comparing a sum of areas of the fragment peaks to a calibration line of the standard.

A method for securing qualitative and quantitative information of a high molecular weight additive in a polymer resin sample is disclosed herein. In some embodiments, the method includes separating a fraction of a polymer resin sample using size exclusion chromatography (SEC), wherein the fraction corresponding to a high molecular weight additive, pyrolyzing the fraction in a pyrolysis-gas chromatography/mass spectrometer (Py-GC/MS) to obtain a mass spectrum of the pyrolyzed fraction; identifying a structure of the high molecular weight additive by comparing m/z values for fragment peaks in the mass spectrum to m/z values for fragment peaks in a mass spectrum of a standard, and determining the amount of the high molecular weight additive in the polymer resin sample, relative to the total weight of the polymer resin sample by comparing a sum of areas of the fragment peaks to a calibration line of the standard.

The present disclosure provides a method for analyzing an additive in a water-based polymer sample, comprising the steps of: (S1) putting the water-based polymer sample containing a polymer, the additive, and water as a solvent into a vial; (S2) putting a porous pouch containing a superabsorbent polymer (SAP) into the vial to absorb the water into the superabsorbent polymer; (S3) removing the porous pouch from the vial and collecting the concentrated polymer sample remaining in the vial; and (S4) performing a pyrolysis gas chromatography (Py-GC)/mass spectrometer (MS) analysis by introducing the concentrated polymer sample to the Py-GC/MS.

The present invention relates to a device and a method for evaluating performance of a deodorant using a superabsorbent polymer (SAP), and the device and method are capable of quantitatively evaluating deodorant performance by collecting ammonia adsorbed to deodorant materials including the SAP and measuring the amount of ammonia thereof.

Polymer makeup is analyzed by performing a liquid chromatographic analysis using a mobile phase containing at least one non-solvent S1 for the polymer and at least one solvent S2 for the polymer, wherein the volume proportion of the solvent S2 varies stepwise during the elution process, and the steps alternate between increasing and decreasing solvent content.

Tracing subterranean fluid flow includes providing a first polymeric tracer to a first injector, collecting a first aqueous sample from a first producer, and assessing the presence of the first polymeric tracer in the first aqueous sample. The first polymeric tracer includes a first polymer formed from at least a first monomer. The presence of the first polymeric tracer in the first aqueous sample is assessed by removing water from the first aqueous sample to yield a first dehydrated sample. pyrolyzing the first dehydrated sample to yield a first gaseous sample, and assessing the presence of a pyrolization product of the first polymer in the first gaseous sample. The presence of the pyrolization product of the first polymer in the first gaseous sample is indicative of the presence of a first subterranean flow pathway between the first injector location and the first producer location.