Quality Control of Raw Materials and Formulations in Construction Industry

Importance of the topic

Modern construction materials rely on precise control of both inorganic and organic components to achieve desired performance in infrastructure projects. Organic admixtures such as superplasticizers and hydrophobic agents play a critical role in optimizing workability, mechanical strength, and durability of concrete, asphalt, and polymer-modified formulations. Ensuring the identity and purity of these additives, as well as the correct composition of final mixtures, is essential for product consistency, regulatory compliance, and competitive advantage.

Study objectives and overview

This application note demonstrates how Fourier-Transform Infrared (FT-IR) spectroscopy, employing Attenuated Total Reflectance (ATR) sampling, can be applied to incoming goods inspection, quality control of formulations, and reverse engineering of competitive products in the construction industry. Key goals include establishing reliable identity checks for raw materials, quantifying specific components in complex mixtures, and identifying unknown chemical species in proprietary or failure analysis scenarios.

Methodology

Samples of raw materials and finished formulations are measured directly on a diamond ATR crystal without any chemical pretreatment or consumables. Infrared spectra, representing unique chemical “fingerprints,” are acquired in seconds. Spectral libraries and automated comparison algorithms enable rapid matching against reference batches, while integration of characteristic absorption bands facilitates quantitative analysis.

Instrumentation

• ALPHA II FT-IR spectrometer (Bruker) equipped with monolithic diamond ATR crystal (1.5 × 1.5 mm).
• OPUS software for spectral acquisition, library search, mixture analysis, and quantitative calibrations.

Main results and discussion

1. Incoming goods control: Hydroxypropyl methylcellulose (HPMC) samples were compared against a reference spectrum, yielding a correlation of 99.9%, well above the 99% acceptance threshold.
2. Quantification of TPO in bitumen/limestone mixtures: By integrating the absorption band at 973 cm⁻¹ specific to thermoplastic polyolefin (TPO), a linear calibration curve was established, enabling determination of TPO content (5–15%) in less than one minute per sample.
3. Reverse engineering of polymerization initiators: An unknown liquid formulation was analyzed via library search and mixture deconvolution. Two components—di-tert-butylperoxide (81%) and tert-butyl perbenzoate (19%)—were identified with near-perfect spectral match.

Benefits and practical applications

• Rapid identity verification of organic raw materials prevents mix-ups and ensures consistent quality.
• Quantitative analysis of admixture content in complex formulations supports product development and regulatory reporting.
• Non-destructive, reagent-free ATR sampling reduces analysis time and operational costs.
• Mixture analysis capability facilitates competitive benchmarking and failure investigation.

Future trends and opportunities

Advances in spectral database expansion, chemometric algorithms, and enhanced ATR crystal materials will further extend FT-IR applicability in construction analytics. Integration with robotics and cloud-based LIMS platforms may enable real-time, on-site monitoring of material properties. Emerging infrared detector technologies promise improved sensitivity for trace admixture detection and moisture quantification.

Conclusion

FT-IR spectroscopy with ATR sampling on the ALPHA II platform offers a versatile, fast, and reliable solution for quality control of raw materials and formulations in the construction industry. Its ability to identify, quantify, and deconvolute complex mixtures complements traditional XRF and XRD techniques, supporting robust QC workflows, product development, and competitive analysis.

Reference

Bruker Optics Application Note AN M138: Quality Control of Raw Materials and Formulations in Construction Industry