The Process of Annealing Plastics
Leave a CommentAlthough the chemical-mechanical properties of plastic are largely determined by their chemical composition, their properties can be modified via heat treatment. One of the most commonly used heat treatment methods to alter the mechanical properties of plastic is annealing.
NYLON – WHY ARE THERE SO MANY AND WHAT ARE THE DIFFERENCES?
Leave a CommentNylon – chemically polyamide (PA, not to be confused with polyimide, PI) was invented in 1935 by DuPont’s Wallace Carothers (PA 6/6). Nylon 6 (PA 6, extruded), or polycaprolactam, was developed by Paul Schlack at IG Farben to reproduce the properties of nylon 6/6 without violating DuPont’s patent. Initially used in fibers to replace silk […]
UHMW-PE – VERSIONS, USES, LIMITATIONS
Leave a CommentUltra High Molecular Weight Polyethylene (UHMW) is one the most widely used thermoplastic materials today. It is defined as having a minimum molecular mass (molecule length) of 3.2 million; some resins go as high as 7.5 million (for reference, HDPE = ~1MM, LDPE = ~500,000) UHMWPE advantages in its virgin form: odorless, tasteless, and nontoxic […]
Lubrication Issues? Get the Grease Out!
Leave a CommentSELF LUBRICATING MATERIALS CAN HELP! Either as an OEM making equipment, or as an end user, lubrication of moving parts is a major consideration – and ongoing cost – in the life of the equipment. Do you find yourself buying more lubricants than you should, or replacing “friction and wear” parts too frequently? Grease is […]
Designing parts with Coefficient of Linear Thermal Expansion in mind
Leave a CommentMost materials will expand when heated and shrink when cooled. Consider expansion joints on bridges – even concrete with rebar will move with temperature changes. The coefficient of lineal thermal expansion is used to calculate how much expansion or contraction will occur when a plastic part is heated or cooled. The lower the figure, the […]
Failure Analysis of Thermoplastic Parts
Leave a Comment“The part failed!” All plastic parts suppliers have received this frantic call and while you want an explanation and immediate solution, it’s critical to find out exactly what went wrong before beginning to determine how to address the problem. First, it’s important to know that most failures are due to a series of events. The […]
ANNEALING OF THERMOPLASTICS – WHAT IS IT, WHY DO IT?
Leave a CommentANNEALING OF THERMOPLASTICS – WHAT IS IT, WHY DO IT? Click to Expand Thermoplastic stock shapes and parts are produced by several methods – all create some level of stress in the material, which needs to be reduced for several reasons. The process most of these shapes undergo is called “annealing”. The process is […]
Acetal- Why Two Types?
Leave a CommentAcetal, an extremely popular engineering thermoplastic also known as POM (polyoxymethylene), comes in two basic types: homopolymer (POM-H) and copolymer (POM-C). While either one will work in over 95% of the applications, it’s important to know the differences. Historically, homopolymer (widely known by its DuPont tradename “Delrin®) was the preferred type in North America; in […]
PEEK – The ‘Swiss Army Knife’ of Plastics
Leave a CommentPolyetheretherketone (PEEK) is an engineering thermoplastic with an unusual combination of properties- high mechanical strength, fatigue and creep resistance, excellent chemical resistance, and the ability to perform in high temperatures. It is so robust and does so many things well, it is the most utilitarian ‘Swiss Army Knife’ in the high performance material thermoplastic group. […]
What is Nylon?
Leave a CommentNylon is a versatile synthetic plastic fiber used in everything from stockings to toothbrush bristles to industrial wear components. Introduced as an alternative to silk in the 1930s, the plastic is a long, heavy chain of repeating polymer patterns—including diamine acid and dicarboxylic acid—known for its easy combination with other materials. Depending on which material […]