Terahertz Spectroscopy Shock Wave Loading Polymer Characterization

The patent merges a shock wave loading system with a terahertz time-domain spectroscopy system into a single integrated apparatus. The loading system applies ultrafast shock waves to the polymer sample while the spectroscopy system simultaneously probes molecular conformational changes through terahertz wave transmission. This combination enables concurrent measurement of mechanical response and molecular structure under dynamic loading conditions, resolving the contradiction between detection capability and system complexity by creating a unified measurement platform.

The patent uses terahertz waves as an intermediary probe to detect molecular conformational changes indirectly. Rather than attempting to directly observe molecular rearrangements under shock loading, the terahertz spectroscopy measures changes in the optical properties (refractive index, absorption) of the polymer, which serve as mediators that reflect underlying molecular structural changes. This intermediary approach enables molecular-level characterization without requiring direct mechanical access to individual molecules.

The patent employs periodic pulsed shock waves to dynamically load the polymer sample at controlled intervals. Each shock wave pulse generates a transient high-strain-rate loading event, followed by a recovery period. This periodic action allows the system to capture dynamic material response at different stages of deformation while maintaining controlled loading conditions. The time-domain spectroscopy similarly uses pulsed terahertz waves to probe the sample at specific time points during and after each shock event, enabling reliable molecular characterization despite the dynamic nature of the loading.

The patent applies preliminary controlled loading through shock waves before conducting the spectroscopic measurement. By pre-loading the sample with a known shock wave profile, the system establishes a controlled deformation state that serves as the basis for subsequent molecular characterization. This preliminary action ensures that the material is in a well-defined mechanical state when probed by terahertz waves, improving the reliability of molecular measurements under dynamic conditions.

The patent replaces traditional mechanical loading systems with a shock wave-based loading mechanism driven by laser-induced plasma. Instead of using conventional actuators or mechanical grips to apply load, the system uses optical energy to generate shock waves that propagate through the sample holder and apply controlled stress to the polymer. This substitution eliminates mechanical interference with the spectroscopy measurement path and enables cleaner separation of loading and probing functions, reducing measurement difficulty while preserving molecular information.

The patent maintains continuous terahertz spectroscopy probing throughout the dynamic loading process. Rather than interrupting the measurement to apply load or vice versa, the system continuously transmits terahertz waves through the sample during shock wave application. This continuity ensures that molecular conformational changes are captured without interruption, preserving complete information about the dynamic evolution of polymer structure under load while the automated coordination of loading and measurement reduces operational difficulty.