What Is Plastic Testing? A Complete Guide to Plastic Identification & Analysis

Plastic testing examines a polymer’s structure, composition, and performance to determine what a material is made of, how it behaves, and whether it’s suitable for a specific application. Unlike metals, plastics are complex engineered materials—additives, fillers, colorants, stabilizers, and processing conditions all influence final performance. Two plastics that look identical can have completely different chemical profiles or mechanical properties.

At its core, plastic testing answers critical questions: What is this material? Is it contaminated? Why did it fail? For manufacturers, suppliers, and engineers, these answers impact safety, durability, regulatory compliance, and product reliability.

Modern industries increasingly rely on analytical testing, which reveals chemical fingerprints, thermal behavior, and microscopic defects that visual inspection can’t detect. Whether a product unexpectedly cracked, discolored, degraded under heat, or arrives as unlabeled resin from a supplier, plastic testing provides clarity and proof-based decisions.

Even small variations in polymer composition can dramatically change how a product performs. An incorrect resin blend might crack instead of flex. A heat-sensitive material might deform under normal use. A supplier substitution could reduce lifespan or violate compliance standards.

For manufacturers, plastic testing protects three critical goals:

• Performance: Ensuring the polymer behaves as expected during real-world use
• Consistency: Confirming every batch meets requirements before production
• Safety & Compliance: Avoiding product recalls, warranty failures, and regulatory issues

Testing is essential when problems occur. If something breaks, discolors, warps, or shows unexpected wear, analytical testing reveals whether the issue came from poor material selection, processing errors, contamination, or aging. These insights allow engineers to correct the root cause—preventing repeat failures instead of relying on trial-and-error.

Alttran approaches plastic testing with a scientific, laboratory-driven focus centered on identification, characterization, and failure analysis. Instead of only measuring how a plastic performs under force, Alttran’s analytical methods uncover what the material is made of and why it behaves a certain way.

Because Alttran already operates a sophisticated rubber testing lab, expanding into plastics was a natural progression. The same investigative tools used for rubber—FTIR, microscopy, and thermal analysis—provide powerful answers for plastic components and raw materials.

Alttran analyzes a wide range of common polymers including polyethylene, polypropylene, PVC, and engineered materials. Samples can be sent directly to the lab, where testing specialists determine the most effective method to uncover material composition, contamination, or structural concerns.

As demand increases, additional test methods and ISO 17025 accredited procedures will be added. Whether the goal is material identification, troubleshooting, or supplier verification, Alttran provides a reliable and data-driven approach.

Fourier Transform Infrared Spectroscopy (FTIR) is one of the most powerful tools for identifying plastics. Every polymer has a unique chemical “fingerprint.” When infrared light passes through a sample, the material absorbs specific wavelengths based on its molecular bonds. FTIR reads this pattern and compares it to reference libraries, revealing exactly what the plastic is.

FTIR Testing Can Answer:

• Is this polyethylene, polypropylene, PVC, or another polymer?
• Has the material been contaminated or altered?
• Did a supplier substitute an incorrect resin?
• Why does one batch perform differently from another?

Because FTIR works quickly and requires minimal sample preparation, it’s ideal for fast turnarounds and routine quality checks. At Alttran, this test is frequently combined with microscopy and thermal analysis when deeper investigation is needed.

Thermogravimetric Analysis (TGA) measures how a plastic changes as it’s heated, revealing critical information about thermal stability and chemical makeup. As temperature increases, plastics lose weight in stages—first from moisture, then plasticizers or additives, and finally from the polymer itself. By tracking these weight changes, TGA shows what a material contains and how it will behave under heat.

TGA Testing Helps Identify:

• Thermal degradation temperature
• Fillers, additives, and stabilizers
• Contaminants or foreign material
• Material composition changes between batches

When customers send a failed part to Alttran, TGA can quickly show whether the polymer was exposed to temperatures above its limits, whether it contained proper additives, or if contamination occurred. The test produces precise data on how a material breaks down, making it valuable for reverse-engineering unknown plastics or matching existing formulations.

Light Optical Microscopy allows Alttran to visually examine plastics at magnified levels—revealing surface defects, fractures, foreign particles, or inconsistencies undetectable with the naked eye. When paired with FTIR or TGA, microscopy helps build a complete, evidence-based picture of why a material behaved the way it did.

Microscopy Can Detect:

• Embedded contaminants or foreign material
• Microcracks or internal stresses
• Poor bonding or mixing of additives
• Defects caused during molding, extrusion, or processing

Because microscopy is fast and non-destructive, it’s often the first step in analyzing a failed part. Alttran’s team uses this method to guide deeper testing—identifying where to analyze the sample for FTIR or TGA evaluation.

When a plastic part breaks, warps, discolors, or fails in use, the root cause is rarely obvious. Alttran combines FTIR, microscopy, and TGA to investigate what happened inside the polymer. If a product cracked, microscopy may reveal internal voids or weak bonding. If a supplier changed the formula, FTIR will detect a different polymer or missing additives. If a part degraded under heat, TGA will show whether the resin lacked proper stabilizers.

Common Problems Failure Analysis Can Solve:

• Material becomes brittle or cracks
• Discoloration, streaking, or contamination
• Unexpected softening, melting, or deformation
• Supplier material doesn’t match specifications
• Aging, environmental exposure, or chemical attack

Instead of guessing why a failure happened, manufacturers get definitive explanations supported by laboratory data. This reduces scrap, avoids repeated breakdowns, and protects product performance. For companies facing warranty claims or supplier disputes, documented lab results provide the proof needed to move forward confidently.

Alttran’s analytical capabilities cover a broad range of polymers, from commodity plastics to specialized engineered materials. The lab frequently works with common resins and blends used in industrial, consumer, and packaging applications.

Current Capabilities Include:

• Polyethylene (PE)
• Polypropylene (PP)
• PVC and vinyl-based plastics
• Polystyrene and modified styrenics
• Filled or reinforced compounds
• Unknown or unlabeled plastic components

As this service expands, additional polymers are being incorporated into Alttran’s reference libraries and analytical methods. This allows customers to send unknown materials or failed parts with confidence that the lab can accurately determine what the polymer is and why it stopped performing as intended.

Each test method is performed by trained laboratory specialists using calibrated instruments, controlled procedures, and traceable reference materials. Although Alttran’s core plastic capabilities currently focus on analytical testing, the lab is working toward ISO 17025 accreditation for additional test methods.

What Customers Can Expect:

• Clear, organized reports with test data and interpretation
• Identification of the polymer and, when relevant, additives or contaminants
• Documentation that can be shared with suppliers, engineering teams, or quality departments
• Fast turnaround and communication during testing

This documentation becomes proof—verifying that incoming materials match specifications, confirming supplier substitutions, or explaining how failures occurred.

Alttran delivers fast, data-driven plastic analysis rooted in proven laboratory methods. By combining FTIR, TGA, and optical microscopy, the team can identify polymers, diagnose contamination, uncover processing issues, and explain why parts failed. This clarity helps manufacturers protect quality, prevent repeat failures, verify suppliers, and confidently choose the right material.

With ongoing expansion, new capabilities on the horizon, and a commitment to accurate, documented results, Alttran is building a plastic testing program designed to serve a wide range of industries. For customers who need real answers—not assumptions—Alttran offers a reliable path forward based on science, expertise, and experience.