MATERIALS KNOW HOW

Materials Know How

A Processor's Most Important Job, Part 7: Reviewing Crystallinity

There are several process-related issues that influence crystallinity besides cooling rate. Let’s examine a few.
#processingtips #bestpractices

Materials Know How

A Processor's Most Important Job, Part 6: Long-Term Effects

The importance of mold temperature to the development of the desired polymer crystalline structure becomes absolutely crucial in the case of high-performance materials.
#Elastomers

Materials Know How

A Processor's Most Important Job, Part 5: POM Polymers

Using a mold temperature above a polymer’s Tg ensures a degree of crystallinity high enough to provide for dimensional stability, even if the part must be used at elevated temperatures. But POM is an exception. Why?
#processingtips #bestpractices

Materials Know How

A Processor’s Most Important Job, Part 4: Mold Temperature

Engineering polymers require higher mold temperatures to achieve their ideal structure. The temptation to turn down the mold temperatures can hurt part performance.
#bestpractices #polyolefins

Materials Know How

A Processor’s Most Important Job, Part 3: Unintended Consequences

Processors are often expected to compensate for ill-advised decisions made earlier in the product-development process. In the case of shrinkage, one of the most common ‘fixes’ is to simply reduce the mold temperature.
#processingtips #bestpractices #Elastomers

Materials Know How

A Processor’s Most Important Job, Part 2: Crystallinity

Process conditions help determine the difference between the maximum degree of crystallinity that can be achieved in a polymer and the degree that is present in a molded part.
#processingtips #bestpractices

Materials Know How

A Processor’s Most Important Job, Part 1: Molecular Weight

Many processors don’t realize that preserving material characteristics is crucial to product success and failure. The focus here is on molecular weight.
#processingtips #bestpractices

Materials Know How

Materials: Cycle Time—Science vs. Rules of Thumb, Part 6

This installment—on elastomers—completes a series, whose theme is to bring more science to the discipline of molding. The overall message: Ask a lot of questions whenever someone posits this or that ‘rule of thumb’ about processing.
#scientificmolding #processingtips #bestpractices

Injection Molding

Materials: Cycle Time: Science vs. Rules of Thumb—Part 5

Let’s examine the behavior of semi-crystalline materials that never reach their glass-transition temperature as they cool.
#scientificmolding #processingtips #bestpractices

Materials Know How

Cycle Time: Science vs. Rules of Thumb—Part 4

While laboratory tests are helpful in determining how polymers behave, you must remember the fundamental differences between laboratory measurements and the real world of plastic processing. Let’s examine semi-crystalline polymers here.
#scientificmolding #processingtips #bestpractices