| Project Background

The glass transition temperature (Tg) is the critical transition point at which an amorphous or semi-crystalline polymer changes from a hard and brittle glassy state to a soft and elastic state, determining the flexibility, impact resistance, and dimensional stability of the material at room temperature. Mastering Tg is of great significance for predicting the low-temperature brittleness of materials, selecting the applicable temperature range (such as maintaining the elasticity of rubber seals in cold regions), and designing the curing process of thermosetting resins. It is the theoretical basis for regulating the performance of polymer products.

| Project Overview

This test is measured by differential scanning calorimetry (DSC), static thermomechanical analyzer (TMA), and dynamic thermomechanical analyzer (DMA). The DSC method measures the change in the power difference or heat flow difference between the target substance and the reference substance by controlling the programmed temperature. The Tg of amorphous or partially crystalline polymers is determined by the height of the specific heat capacity step and the width of the glass transition region in the DSC curve.

The TMA method is a method to explore the relationship between the size of the experimental material and temperature change by applying a constant force. It mainly measures the intersection of the tangents of the curve of the amorphous or partially crystalline polymer before and after the glass transition to determine the value of Tg.

The DMA method is a method to study the change of the mechanical properties and viscoelasticity of materials with temperature or frequency under cyclic vibration stress. There are mainly three ways to represent the Tg of polymers measured by the DMA method:

The temperature corresponding to the extrapolated starting point of the curve before and during the change on the storage modulus (E') curve is taken as Tg, which is related to the mechanical failure of the material;

The peak temperature of the loss modulus (E''), which is related to the change in the physical properties of the polymer and reflects the initial temperature of the movement of polymer molecular segments;

(3) The peak temperature of the loss factor (Ttanδ), which represents the damping performance of the material.

| Test Objective

1. Meeting industry standard requirements and verify compliance;

2. Research and innovation;

3. Failure analysis and root cause tracing.

| Testing Standards

ISO 11357-2 Plastics - Differential scanning calorimetry (DSC) - Part 2: Determination of glass transition temperature and step height

GB/T 19466.2 Plastics - Differential scanning calorimetry (DSC) - Part 2: Determination of glass transition temperature

IPC TM-650 2.4.24 Testing of glass transition temperature and Z-axis thermal expansion by TMA method

ISO 11359-2 Plastics - Thermomechanical analysis (TMA) - Part 2: Determination of linear thermal expansion coefficient and glass transition temperature

ASTM D7028 Standard test method for determining the glass transition temperature (DMA-Tg) of polymer-matrix composites by dynamic mechanical analysis (DMA)

| Service Products / Fields

Consumer electronics, automotive electronics, rubber industry, plastics industry, electronic packaging, biodegradable materials, coatings and adhesives, optoelectronic display technology, etc.

| Project Advantages

1. DSC: The test temperature range is from -150°C to 600°C. It has advantages such as fast speed, small sample usage, and simple sample preparation, but it is easily affected by thermal history and curing time;

2. TMA: The test temperature range is from -100°C to 900°C. It has advantages such as high sensitivity and convenient sample preparation, but it requires the material to have a sufficiently high viscosity above Tg, and the surface should be smooth and parallel. Secondly, it is affected by the thermal history of the sample and the possible softening point;

3. DMA: The test temperature range is from -100°C to 400°C. It is the most sensitive method for determining Tg. There is no need to eliminate the thermal history of the material, but it has relatively strict requirements on the sample size and is suitable for determining the Tg of some highly crystalline and highly cross-linked composite materials and filled materials.

| MTT Advantages

1. Professional Team: A team of highly experienced testing engineers and technical experts.

2. Advanced Equipment: Equipped with internationally leading testing instruments to ensure accuracy and reliability of results. The requirements for the sample are low, and regular sheet-shaped samples are sufficient; the testing time is fast, and data can be obtained within one minute at the fastest.

3. Efficient Service: Rapidly respond to customer needs and provide one-stop, high-efficiency inspection services.

4. Authoritative Certification: The laboratory is certified by ISO/IEC 17025, ensuring that test reports have international credibility.