EP Topics

Types of Degradation of Iupizeta EP Through Molding

Iupizeta EP, being a specialty polycarbonate material, may undergo thermal degradation or hydrolysis depending on molding conditions. These forms of degradation can lead to molding defects due to reduced strength, discoloration, and gas generation. To ensure stable molding, it is essential to minimize these degradation reactions as much as possible.

Basics

Thermal Degradation Mechanism and Countermeasures

Thermal degradation refers to a phenomenon in which molecular chain scission occurs due to thermal energy and the influence of trace resisuals of oxygen dissolved in the molten resin. As a result, it can cause reduced strength (brittleness), resin discoloration, and molding defects due to gas generation.

Basics

Hydrolysis Mechanism and Countermeasures

Hydrolysis is a phenomenon in which materials that contain ester bonds in their molecules—such as polycarbonate and polyester resins—react with water and the bonded sites undergo molecular chain scission.This degradation can cause variations in flowability, reduced strength, and molding defects such as silver streaks, bubbles, drooling, and stringing.Because Iupizeta EP, a specialty polycarbonate material, can undergo hydrolysis even under the influence of trace moisture, proper drying with appropriate equipment and conditions is extremely important.

Basics

Pre-drying Conditions for Iupizeta EP

Iupizeta EP, being a specialty polycarbonate material, requires pre-drying before molding. It has been known that lower drying temperatures result in higher residual moisture content. For precision molding such as small lenses, it is important to reduce the residual moisture content to below 0.01% in order to prevent moisture-related molding defects.Therefore, for Iupizeta EP, drying at 120°C for at least 6 hours (*) is recommended.

Basics

Moisture re-absorption Behavior During Molding and its Countermeasures

Iupizeta EP, a specialty polycarbonate material, when pre-dried, absorbs moisture in a short time and can exceed the recommended range of <0.01% within about 20 minutes at room temperature. In particular, if left in the hopper for extended periods of time, temperature lowers, leading to acceleration of moisture re-absorption.Therefore, using a hopper dryer is effective in suppressing moisture re-absorption after drying.

Basics