The hydroxyl value (HOV) of a polymer, typically reported in mg KOH/g of polymer, is one of the key parameters typically reported in the technical data sheet (TDS) or certificate of analysis (CoA) of polymers containing hydroxyl functionalities. Several methods exist to determine the HOV of polymers, the most common of which is an acid-base titration. While conceptually simple, this approach is in fact elaborate, expensive, and wasteful from both a reagent and solvent perspective. In this application note, we present two quantitative benchtop nuclear magnetic resonance (qNMR) methods, which require very little solvent (deuterated solvents are not required) and small amounts of reagents. One of these methods is appropriate for polymers soluble in organic solvents, such as chloroform, while the other method is recommended for water-soluble polymers.

Selected 2025 Benchtop NMR Highlights

Peer Reviewed Journal
Diazepam quantification in street tablets using benchtop 1H qNMR spectroscopy: Method validation and its application

Polyurethanes App Note
Quality Control Assays of Polyurethane Raw Materials Using Benchtop Nuclear Magnetic Resonance Spectroscopy

PharmaApp Note
USP Monograph using
60 MHz Benchtop NMR - Molar Substitution Determination in Hydroxypropyl Betadex

Sample Experiment
Real-Time 100 MHz Benchtop NMR Monitoring of the Wittig Reaction:
Influence of Aldehyde Activity on Rate and Stereoselectivity

Using the standard addition method, we determine the concentration of sodium acetate in an unknown sample by spiking the sample with known amounts of sodium acetate.

In this blog post, we introduce some of the work we've recently done on the analysis of essential oils using benchtop NMR spectroscopy. Specifically, we've developed some analytical methods for quantitative assays of key components, such as citral, linanyl acetate, linalool, decyl aldehyde, and eucalyptol. The sample preparations are straightforward, and the data can be collected in seconds or minutes, depending on the specific sample. If the contents of this blog post are of interest to our readers, we hope that it will encourage them to read our full peer-reviewed manuscript, which was recently published in the Magnetic Resonance in Chemistry journal, as part of a special issue on quantitative NMR.

Using benchtop NMR, stress testing of pharmaceuticals such as voriconazole under acidic conditions enables scientists to assess chemical stability and detect potential degradation products.

Street drugs are rarely pure, and the rise of complex opioid mixtures poses serious risks to public health. Our latest blog post shows how benchtop NMR combined with Wiley KnowItAll enables forensic labs to rapidly identify opioids like heroin and cutting agents in complex ¹H NMR spectra. Read More.

Check this blog if you want to know more our the Nanalysis-100 flow cell.

‘The spectra were analyzed according to first order’. Does this sound familiar to you? Most of the supporting information documents out there contain this sentence. You find yourself asking ‘why does nobody care about second order effects?’, then check out this high-order blog entry on the topic.

COSY and TOCSY are two complementary 2D NMR experiments that help determine molecular structures by revealing proton-proton connections.

This blog post demonstrates how trifluoroacetic acid can be added to NMR samples to shift signals arising from water or exchangeable protons, which can sometimes overlap with other signals of interest.