Polymer Failure Analysis

Alfa Chemistry, with over two decades of experience in analytical chemistry and material science, employs polymer failure analysis as a strategic approach to drive product reliability, support research and development initiatives, and deliver meaningful insights for actionable quality improvement. The forensic evaluation of the point of failure is the starting point, where observations of regions with stress concentration, cracks, discoloration, or chemical degradation are made. This enables the scientist to determine the most effective analytical methods for a complete failure characterization.

What is Polymer Failure Analysis?

Polymer failure analysis can be described as an analysis to try to determine why a polymeric material (including plastic, elastomer, thermoset, or composite) failed. A polymer failure analysis is part of materials science and engineering. The purpose of a polymer failure analysis is to discover the root cause of failure. In other words, is the failure of the polymer product inherent to the material itself, was it caused by external environmental conditions (chemical or physical), or was the product used in a way that was beyond the intended design of the material.

Reasons Why Polymers Fail

Failures in polymers can be attributed to various mechanical, chemical, and environmental factors. Here are some of the key reasons for such failures:

• Material Selection and Design Flaws: Incorrect selection of raw materials or suboptimal design choices may lead to inadequate mechanical properties, brittleness, or susceptibility to chemical attack.
• Contamination and Inclusions: The presence of foreign particles, moisture, or residual solvents can cause cracks or act as catalysts for degradation reactions.
• Chemical Attack and Oxidative Degradation: Exposure to ozone, UV radiation, or aggressive chemicals can break polymer chains, making them brittle and prone to cracking.
• Thermal and Mechanical Stress: Excessive temperatures (above the glass transition temperature) or mechanical loads can cause fracture or deformation.
• Environmental Factors: Humidity, temperature fluctuations, and weathering can contribute to polymer degradation, leading to embrittlement, surface cracking, or discoloration.
• Processing Defects: Manufacturing issues like molding defects, incomplete curing, residual stresses, weld lines, or improper annealing can introduce weak points or defects that accelerate failure.
• Additives and Composite Issues: Inappropriate additives or poorly dispersed reinforcing fibers in composites can negatively impact mechanical properties and chemical resistance.

Alfa Chemistry regularly analyzes these failure modes to identify recurring patterns and develop prevention strategies for specific applications, ranging from packaging films to aerospace composites.

Testing for Root Cause

Root cause analysis in polymer failure involves a systematic evaluation of material properties and defect characterization. Key steps include:

• Visual & Stereo Microscopy: Allows for nondestructive examination of cracks, voids, blisters and surface anomalies. Stereo microscopy permits three-dimensional visualization and location of mechanical failure sites.
• Molecular Weight Analysis: Gel permeation chromatography (GPC) provides molecular weight and molecular weight distribution (polydispersity) information and can be used to determine the level of degradation or chain scission as compared to standards.
• Thermal Analysis: Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) can be used to determine thermal stability, glass transition temperature and/or melt temperature, crystallinity, and total inorganics.
• Mechanical Testing: Tensile, compression and impact tests can be used to determine stiffness and elongation and give insight into the resistance to deformation (mechanical failure point).
• Chemical Composition and Trace Analysis: Fourier-transform infrared spectroscopy (FTIR), FTIR microscopy and mass spectrometry (GC-MS, LC-MS, PYMS) techniques can be used to detect chemical heterogeneity, contaminants and composition of additives.
• Physical and Environmental Testing: Weathering chambers, UV exposure and environmental stress cracking testing are available for simulation of service conditions.

Alfa Chemistry integrates these analytical methods to produce a comprehensive failure profile, guiding corrective actions and preventive strategies.

Polymer and Plastic Failure Analysis Testing

Failure analysis testing encompasses multiple categories to identify specific causes and assess material integrity:

• Additives for Polymers and Elastomers: Qualification and quantification of stabilizers, plasticizers and fillers.
• Mechanical Failure Testing: Fracture, tensile and fatigue testing
• Chemical Degradation: Oxidative, thermal and environmental degradation testing
• Fibre-Reinforced Composite Evaluation: Delamination, fiber breakage and matrix-fiber interface
• Surface Defects: Voids, blisters, nibs, weld lines, adhesion failures
• Discoloration, Odor and Outgassing Analysis: Polymer odor detection, tainting, and volatile emissions.

The individual tests selected depend on the type of polymer, the service conditions and the application.

Polymer Failure Analysis Methods

Analytical tools used for polymer failure analysis at Alfa Chemistry:

• GPC (Gel Permeation Chromatography): To assess the molecular weight distribution and potential polymer degradation.
• Stereo and Optical Microscopy: For non-destructive imaging of cracks and surface features.
• FTIR-Microscopy: Chemical mapping to reveal compositional heterogeneity and phase inconsistencies.
• Mass Spectrometry (MS): For identification of unknown chemical species, additives, and contaminants.
• Thermal Analysis (DSC/TGA): To determine thermal transitions, decomposition temperatures, and material stability.
• Mechanical and Physical Testing: Tensile, stiffness, impact, and fatigue properties.
• Environmental Stress Simulations: Accelerated aging to predict service life under extreme conditions.

With these capabilities we provide both root cause analysis and support the design of robust high performance polymeric products.

Polymer Failure Analysis Sample Requirements

Advantages of Alfa Chemistry in Polymer Failure Analysis

Alfa Chemistry distinguishes itself through decades of expertise, state-of-the-art analytical facilities, and a multidisciplinary approach to polymer science. Key advantages include:

Frequently Asked Questions (FAQ)

With many years of experience in polymer failure analysis, Alfa Chemistry's team of experts and state-of-the-art laboratory are at the forefront of analyzing, mitigating, and preventing polymer failures. By employing advanced testing, chemical characterization, and mechanical analysis, Alfa Chemistry is committed to delivering clear, actionable, and definitive results. In addition to chemical analyses, Alfa Chemistry is also experts in mechanical testing and polymer analysis for failure prevention and analysis.