This article is a simple set of notes and links for some research into the practicality of spectroscopy methods for use with plastic polymers.

“Polycarbonates contain several phenyl-based molecular groups, which are very energy-rich due to the π electrons of the double bond in the ring. In fluorescence, electrons can be lifted into higher energetic orbitals (S1) from a high-energy ring system using hard radiation. This energy level is unstable, and the electron leaves this orbital emitting photons (luminosity = fluorescence).” [1]

ABS-PC

“PC/ABS (polycarbonate / acrylonitrile-butadiene-styrene terpolymer blend) is a thermoplastic alloy of (PC) polycarbonate and (ABS) acrylonitrile-butadiene-styrene. Both PC/ABS materials are well known amorphous plastics. Alloying these two materials enhances processability, and provides non-halo flame retardancy.

Polycarbonate (PC) is a rigid thermoplastic that provides clarity, toughness, and good heat resistance. By itself, polycarbonate has reasonable resistance to burning, and that resistance increases by adding flame retardants that are typically halogen-containing. Acrylonitrile-butadiene-styrene is a well know rigid thermoplastic that offers both moderate impact and moderate chemical resistance. The heat resistance of acrylonitrile-butadiene-styrene is lower than that of polycarbonate. Like polycarbonate, halogen containing additives are used to increase resistance to burning.” [2]

ABS

“Acrylonitrile butadiene styrene (ABS) (chemical formula (C₈H₈)_x·​(C₄H₆)_y·​(C₃H₃N)_z ) is a common thermoplastic polymer. Its glass transition temperature is approximately 105 °C (221 °F).^[4] ABS is amorphous and therefore has no true melting point.

ABS is a terpolymer made by polymerizing styrene and acrylonitrile in the presence of polybutadiene. The proportions can vary from 15% to 35% acrylonitrile, 5% to 30% butadiene and 40% to 60% styrene. The result is a long chain of polybutadiene crisscrossed with shorter chains of poly(styrene-co-acrylonitrile). The nitrile groups from neighboring chains, being polar, attract each other and bind the chains together, making ABS stronger than pure polystyrene. The acrylonitrile also contributes chemical resistance, fatigue resistance, hardness, and rigidity, while increasing the heat deflection temperature. The styrene gives the plastic a shiny, impervious surface, as well as hardness, rigidity, and improved processing ease. The polybutadiene, a rubbery substance, provides toughness and ductility at low temperatures, at the cost of heat resistance and rigidity.^[3] For the majority of applications, ABS can be used between −20 and 80 °C (−4 and 176 °F), as its mechanical properties vary with temperature.^[5] The properties are created by rubber toughening, where fine particles of elastomer are distributed throughout the rigid matrix.” [3]

Additional Concepts:

Everything you need to know about PID Sensors

“PID stands for “Photo-Ionization Detector”. PID (Photoionization Detection) sensors are essential tools for monitoring air quality and can be incorporated into a hand-held, personal, or fixed detector for the detection of volatile organic compounds (VOCs) and some inorganic compounds.

ION Science sensors can detect VOCs down to parts-per-billion (ppb) and up to thousands of parts-per-million (ppm). In this article ‘Everything you need to know about PID Sensors’, we’ll answer some frequently asked questions about PID sensors to help you better understand their applications, advantages, and importance across various industries.” [4]

Refs

1. PC is suitable for fluorescence – https://www.shimadzu-webapp.eu/magazine/issue-2020-2_en/how-much-fluorescence-does-a-polymer-show-during-quality-control/
2. ABS-PC indeed contains Polycarbonates – https://prlresins.com/products/pc-abs-resin/#:~:text=PC%2FABS%20(polycarbonate%20%2F%20acrylonitrile,provides%20non%2Dhalo%20flame%20retardancy.
3. ABS – https://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene
4. PIDs for VOC detection (likely associated with defects) – https://ionscience.com/usa/news/everything-you-need-to-know-about-pid-sensors/#:~:text=PID%20(Photoionization%20Detection)%20sensors%20are,VOCs)%20and%20some%20inorganic%20compounds.