Very interesting lecture. Thank you very much professor. Please I have question hope to get some answer . If the results of storage and loss modulus plot dos not appear the point of cross over point what that mean and how we can make improvement to get this point . what is this cross over point mean , it is represent longest relaxation time or minimum relaxation time Kind Regard
Grouping materials as dilute solutions, concentrated suspensions, or gels, permits the following generalizations with respect to their storage and loss moduli. 1. With dilute solutions, G′′ is larger than G′ for the entire frequency sweep. However, at the larger frequencies, the moduli approach each other. 2. For concentrated solutions, G′′ starts greater than G′ and at some point, they cross over. This cross over point is a function of the frequency and may be an important parameter when describing the material. 3. For gels, G′′ and G′ are independent of frequency and run parallel to each other with G′ being larger than G″. Generally, the gel point is identified when the storage and loss moduli cross over, However, gelation point should be independent of anything. At the gel point, G″ and G′ are parallel to each other regardless of frequency, ω (strong gel).
Very interesting lecture. Thank you very much professor. Please I have question hope to get some answer . If the results of storage and loss modulus plot dos not appear the point of cross over point what that mean and how we can make improvement to get this point .
what is this cross over point mean , it is represent longest relaxation time or minimum relaxation time
Kind Regard
Grouping materials as dilute solutions, concentrated suspensions, or gels, permits the following generalizations with respect to their storage and loss moduli.
1. With dilute solutions, G′′ is larger than G′ for the entire frequency sweep. However, at the larger frequencies, the moduli approach each other.
2. For concentrated solutions, G′′ starts greater than G′ and at some point, they cross over. This cross over point is a function of the frequency and may be an important parameter when describing the material.
3. For gels, G′′ and G′ are independent of frequency and run parallel to each other with G′ being larger than G″. Generally, the gel point is identified when the storage and loss moduli cross over, However, gelation point should be independent of anything. At the gel point, G″ and G′ are parallel to each other regardless of frequency, ω (strong gel).
4:40 Mooney Viscosity
21:00 Molecular weight distribution (MWD)