I was really pleased to hear from Susan from Wacker. They’re one of the leading silicone corporations worldwide and I’ve read through their reports time and time again. I appreciated the information that was shared in a way that I could understand them. Sometimes the meanings get lost on me with all of the Scientific languages.
SUSAN J. CASSAR
CREATING TOMORROW’S SOLUTIONS
Wacker Chemical Corporation
3301 Sutton Rd
Adrian, MI 49221 USA
Tel. toll-free 888 922-5374
Wacker Michigan Plant since 2000
Technical Services Manager at Wacker Chemical Corporation
Skills: Troubleshooting, Construction, Coatings, Polymers, Additives, Teaching, Creativity, Materials, Cross-functional Team Leadership, Product Development
Polymer Chemistry, R&D, Raw Materials, Manufacturing, Chemistry, Key Account Management, Market Development.
Bachelors in Chemistry
WACKER CHEMICAL CORPORATION
“Thank you for your inquiry dated February 4, 2017, and your interest in WACKER.
I will do my best to answer your questions:
As Wacker only manufactures silicones, I can best speak regarding the properties of these materials.”
1) How many ways are there to make “Medical grade silicone”?
There are many ways to make a medical grade silicone. All the designation really means is that the supplied silicone meets certain medical testing certifications. There are a few different certification systems (such as USP VI and ISO 10993) which have different types of tests.
2) Is there a way to tell if a silicone is “food grade” from “medical grade”?
No, you can’t tell by looking at the silicone. Some silicones can be certified to both medical and food uses depending on the testing they have been subjected to. Like there are different tests for “medical” certifications, there are also different tests, and levels of certification, for food applications.
3) In regards to your statement about stretching and silicone turning white –
If the silicone has been tested and certified for food or medical applications, it does not contain any fillers (or any other raw materials) that are considered toxic or harmful to the body under the intended use (i.e. skin contact, not ingestion). However, this phenomenon of color change has been seen in other types of rubbers, such as TPE.
Silicones don’t change color during molding. If the uncured silicone is clear, then the cured silicone part is clear. If the uncured silicone is white, then the cured silicone is white. I have never experienced any silicone that has changed color when pinched, pulled, twisted or stressed in any way. Again, this is something that occurs with natural rubbers like TPE.
5) Is Compression the best way to process a silicone?
Compression molding is one way to process and cure silicone. Other options are Transfer Molding and Injection Molding. Each uses heat and pressure in order to cure the silicone. There is no “best” option. The molding methods vary based on the type of equipment the molder has, and the number and type of part being made. There is no way to tell by looking at a finished part what method of curing or type of equipment was used.
6) Can Silicone withstand high temperature?
Yes, silicones can withstand high temperatures (up to 200C or 400F) with no significant changes in material, so they can easily withstand cleaning by boiling. Other rubbers, such as TPE, cannot handle high temperatures, and therefore boiling would not be recommended.
7) On a sex toy site, someone claimed that a “pure silicone will never be crystal clear and see-through. The extreme stretch and the jelly look of the material means it’s not silicone”. Is this true?
Pure silicone products can be clear. I can not speak to what a molder or manufacturer may add to silicone rubber, or any other type of rubber supplied to them. The retailer may make any claims they want about their product, but the liability also lies with them if anything goes wrong.
If you have additional questions, please do not hesitate to contact us.
SUSAN J. CASSAR