Processing and De-Moulding of Auto Lamp Holders Improved by Siloxane Additive

Dow Corning® MB50-010 Masterbatch is an internal lubricant for GE ULTEM® Polyetherimide (PEI). It is provided in the form of pellets and has 50% of an ultra-high molecular weight siloxane dissolved in DuPont HYTRELL® (MI 11).

The siloxane additive has very good melt flow and allows easy processing of a direction indicator lamp holder. It also simultaneously enables easier mould release for superior throughput and reliable component quality.

Process

Dow Corning® MB50-010 Masterbatch (Figure 1) provides good cavity fill as well as extra slip. The siloxane additive is measured and combined with PEI at 1% by weight. Due to the palletized additive’s ultra-high molecular weight, it does not alter the surface of the finished component, and therefore does not hinder the subsequent coating process in any way.

Dow Corning® MB50-010 Masterbatch

Figure 1. Dow Corning® MB50-010 Masterbatch

The MB50-010 Masterbatch pellets can be dry mixed into the polymer mix with the aid of automated metering without any processing hassles and bleed problems that occur with liquid siloxanes. Another advantage with solid masterbatch is that it enables delivery of siloxanes with a much greater concentration than those found in liquid additives (50% vs. <20%).

When added at concentrations of 0.2-2% to other solutions such as HYTREL or similar polyester elastomers, the siloxanes aid the flow of resin, thereby improving mould fill and minimizing extruder torque, and resulting in a much better quality part, decreased energy consumption, and faster throughput.

When added at concentrations of 2-10%, the MB50-010 Masterbatch provides superior lubricity and abrasion resistance. The Dow Corning MB50-010 Masterbatch can also be added while compounding in a single screw extruder or dry blended at the feed hopper during profile/sheet extrusion, injection moulding, or other traditional thermoplastic processing.

As the Dow Corning MB50-010 Masterbatch is based on a polyester elastomer, it tends to absorb moisture over time, thus may require drying. Drying of the material can be performed up to less than 0.2% moisture content according to the specific application.

A desiccant dryer or a dehumidifying at 80°C (176°F) can also be used for 2-8 h or until the preferred moisture level is attained. If stored unopened at or below 35°C (95°F), the Masterbatch has a usable period of 48 months from the date of production.

Application

The Dow Corning MB50-010 Masterbatch is ideal for use as a slip or release agent in the manufacture of a basic polymer or finished food contact article, meeting the U.S. FDA regulation 21 CFR 177.2600. The polyester elastomer part of the formulation meets the requirement of subpart 177.2600, and the siloxane portion meets the requirement of subpart 181.28.

About Dow Corning Automotive

Dow Corning provides cost-effective solutions for the automotive sector. The company’s Innovative technologies help improve vehicle performance and reduce costs.

Dow Corning offers high-performance specialty products, collaborative problem-solving and technical support with its Dow Corning brand, Molykote brand and Silastic brand specialty materials.

Dow Corning’s innovative materials, application expertise and global support make smart business sense on every level of the value chain. Involved in transportation innovation for more than 65 years, Dow Corning works with customers to develop advanced automotive solutions.

This information has been sourced, reviewed and adapted from materials provided by Dow Corning Automotive.

For more information on this source, please visit Dow Corning Automotive.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type
Submit

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.