Hard and brittle? Soft and pliable? Or somewhere in between? The properties of polymers can vary greatly, and those properties can be tuned to meet a specific customer need. Whether you are considering a polymer for outdoor house paint or for the undercoating of an automobile, its behavior at the different temperatures...
With problem-detecting sensors, wireless connections, cloud-based security and real-time navigation, it’s easy to think that the high-tech features in today’s hot rides are all electronic. That, however, would be overlooking some of the most remarkable technologies that are making cars safer, quieter, less expensive and...
Vinyl acetate monomers (VAM) are essential building blocks for a large number of water-based polymers. Vinyl acetate is prepared from ethylene by reacting it with oxygen and acetic acid over a palladium catalyst. The basic chemical reaction is shown below, along with the chemical structure of vinyl acetate monomer.
Moisture vapor transmission rate, also called water vapor transmission rate (WVTR), is the amount of water vapor that passes through a substance or material over a specific period of time.
Nitrile elastomers are emulsion polymers produced using rubber polymerization techniques. Also known as nitrile emulsions or nitrile latexes, these are dispersions of acrylonitrile and butadiene — or sometimes styrene — in water. Nitrile elastomers are true colloids, defined as a homogenous amorphous substance consisting...
Polymers are unlike other types of materials because of their high molecular weight. Molecular weight is the value used to express the size of a molecule. Water, for example, has a molecular weight of 18 atomic mass units. Polymers are much larger, with molecular weights ranging from tens of thousands up to several million...
Glass certainly seems like a solid substance — it’s hard and brittle at room temperature — but glass exhibits other properties that make it unique, which is why chemists classify it as an amorphous solid. Amorphous solids are those that have short-range order but no long-range order. In this case, order refers to how the...
Styrene-butadiene (SB) latex is a common type of emulsion polymer used in a number of industrial and commercial applications. Because it’s composed of two different types of monomers, styrene and butadiene, SB latex is classified as a copolymer. Styrene is derived from reacting benzene and...
Chemists sometimes describe latex as a colloidal dispersion that remains stable — i.e., the particles that make up the dispersion don’t settle or cream over time. This is accomplished by a combination of ionic and steric stabilization. Keep reading to understand how these two unique mechanisms work.
Chemists who make latexes generally start by understanding how the product will be used. That’s because the end-use application of an emulsion polymer has significant implications for how it’s designed. Knowing the end use helps the chemist develop the right recipe, with all of the right ingredients, that results in an...
It’s convenient to think of polymers as long chains, and, sometimes, that’s accurate. But polymers have a number of complex interactions — between monomers and between polymer chains — that result in recognizable architectures. These architectures can have tremendous impact on the properties of a polymer emulsion being...
Most people are familiar with the concept of melting point — the temperature at which a solid changes into a liquid state. But not all materials have a defined melting point. An amorphous polymer has a glass transition temperature, which is not a single temperature at all but a range of temperatures across which the...
