Thus, there is a need for a simple procedure to address the need to molecular weight determinate of the polymer or biopolymer using a single sample, without having to wait too long for an optimal molecular weight result, and with this procedure requiring only one densimeter and viscometer as well as perhaps a simple equation point such as the Solomon-Ciuta. In many cases, this process cannot be stopped since this would involve economic losses and time delays. Problems can arise when the temperature of the raw material (biopolymer in the production process) must be increased so that it can be pumped through pipes to reach its destination. Quality control in the polymers or biopolymers industry is essential in order to achieve an acceptable product for the consumer. ![]() The method is simple and requires iterative mathematical processing and measurement of intrinsic viscosity at different temperatures. The basic criterion is that the molecular weight does not change with temperature, or at least within one discrete range of temperatures, but that there is hydrodynamic change (intrinsic viscosity). It is therefore necessary to know the change in molecular weight as evidence of a change in the product obtained, as this may create a need to halt the production process, transport, or extrusion. ![]() The M-H parameters are calculated at standardized temperatures and in many cases, these are not useful because of the errors they carry, and it then becomes very difficult to calculate the molecular weight. In the polymer industry, polysaccharides and proteins must circulate through pipes during transport processes where pumps have a very high-energy expenditure and where temperatures must be greatly increased, and at this point calculation of the Mark-Houwink parameters becomes important. The intrinsic viscosity measurements used to calculate the Mark-Houwink (M-H) parameters are generally performed for different molecular weights at a constant temperature, with the standard value of this temperature being 25☌, or else 37☌ in the case of mammalian proteins, or else under theta conditions for polymers and biopolymers.
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