Various types of glass capillary viscometers, especially Ubbelohde-type glass capillary viscometers, are used for the determination of the intrinsic viscosity and other polymer parameters. Both the calculation of the reduced and the inherent viscosity require the concentration value and therefore the intrinsic viscosity is an important parameter as it is an extrapolation to a theoretical zero concentration. However, this state can never be reached in reality and therefore small polymer interactions have to be considered. In this “ideal dilute solution” the concentration approaches zero meaning that the polymer molecules are isolated from each other and only interact with the solvent molecules.
Determination of intrinsic viscosity of polymers free#
A solution free of any interactions between the polymer molecules could only be reached in the state of the “ideal dilute solution”. As the molecular interactions decrease with decreasing concentrations, viscosity measurements are carried out with very dilute solutions. The flow behavior of the polymer solution is highly dependent on the molecular structure of the polymer as well as on interactions of the molecules with each other in solution. One of those is “dilute solution viscometry,” which can determine parameters such as intrinsic viscosity. įor the characterization of synthetic polymers as well as biopolymers, many different techniques are available. In addition, they are used as industrial plastics, clothing fabrics, absorbents, water treatment chemicals, or biosensors in other applications. More specifically, biocompatible and biodegradable biopolymers are suitable for applications such as edible films, emulsions, or packaging materials in the food industry as well as wound dressing materials, medical implants, sutures, or drug transport materials in the pharmaceutical and medical industries. Due to these beneficial properties, biopolymers can be used in different application areas, such as the food, medical, and pharmaceutical industries. In comparison to synthetic polymers, biopolymers offer advantages like well-defined and more-complex structures, (bio)degradability, non-toxicity, and renewability. This definition includes proteins, nucleic acids, and polysaccharides. e., macromolecules that are formed by living organisms). Īccording to IUPAC, biopolymers are substances that are composed of one type of biomacromolecules (i.
To meet this demand for alternative materials for specific applications, many different biopolymers and renewable resource-based biopolymers have been studied and developed. For such materials, these should not only be biodegradable but also be derived from natural resources. Since they are typically derived from fossil raw materials, however, synthetic polymers are increasingly being replaced by biodegradable materials because of environmental concerns. When it comes to applications like food packaging, synthetic polymers are mostly used for them because of certain benefits these polymers offer, including versatility, functionality, affordability, and flexibility. Depending on the type of monomer as well as the size and molecular structure of the polymer molecule, polymers show unique properties. Polymers are macromolecules that are composed of small repeating units called “monomers” (Figure 1). Intrinsic viscosity is used to classify polymers and helps to identify the applications that specific polymers can be used for. Intrinsic viscosity determination is used in the field of polymer chemistry, which is a chemistry subdiscipline that deals with the synthesis of polymers as well as the analysis of a polymer’s structure and properties.
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