High-Accuracy Moisture Testing for Reliable Plastics
Plastics manufacturers need both production quality and speed. The right moisture content in raw materials ensures trouble-free molding as well as smooth surfaces and ideal mechanical properties for finished items.
In plastics manufacturing, incorrect moisture content (MC) in raw plastic pel-lets might not only result in molding issues but final products could also exhibit defects such as splaying, flash and brittleness. In-process MC control of raw materials prior to melting and conversion is therefore crucial for ensuring processing ease and final product quality.
Unlike Karl Fischer titration, for which MC determination requires a laboratory, chemicals and operator know-how, a moisture analyzer is ideal for production environments such as injection molding sites.
ASTM standard D6980-12 “Standard Test Method for Determination of Moisture in Plastics by Loss in Weight” recognizes the use of a halogen moisture analyzer. METTLER TOLEDO’s HX204 is ideal for performing fast, simple and cost-effective moisture analysis and delivers the minute 0.1 mg resolution in accordance with the ASTM standard.
Ensuring repeatable accuracy
With HX204, you achieve accurate and reliable results for plastics moisture determination, even at the extremely low MC percentages (typically <0.2 % MC) of plastic. HX204’s high performance MonoBloc weighing cell (200 g capacity, 0.1 mg resolution) is the foundation of the instrument’s unmitigated accuracy. An innovative hanging weighing pan, and the separation of the load cell from the heating cavity, eliminate adverse thermal effects on the weighing cell providing outstanding repeatability.
A preheating option further enhances repeatability by ensuring the heating cavity is always in the same state at the start of every measurement. Drying method parameters can be optimized to prevent premature switch-off if MC is particularly low or contained moisture might not readily evaporate at the beginning of the measurement process.
To ensure consistency, it is also important to prove instrument accuracy over time. For this purpose, HX204 has a built-in ten-minute program for performance testing using SmartCalTM, METTLER TOLEDO’s certified test substance for moisture analyzers. This rapid testing fulfills the requirements of regulated industries and company audits.
Reporting of both tests and results is supported by A4 and letter-size templates, while HX204’s software also allows you to instantly transfer results to a network via Ethernet or Wi-Fi – ideal for quality-control monitoring. With a large color touchscreen, intuitive user interface and shortcuts for easy access to drying methods, HX204 is perfect for fast MC determination on the plastics production line.