Crosslinks chemical

For all samples, except the vulcanisate of EPDM with 4.6 wt.% ENB and 1.5 phr sulfur, the ratio of the converted number of ENB moieties and the number of chemical crosslinks is around 2.0 ( 0.2). The statistical spread in the ratio of the converted number of ENB molecules and the number of chemical crosslinks is estimated to be 10-15% based on the error in the Raman and NMR data. Furthermore, there might be a systematic error in the crosslink density as determined by NMR, originating from the assumptions made in calculating the number of chemical crosslinks from the total number of crosslinks (chemical and entanglements). 

Petersen, N., Crosslinking chemicals and the chemical principles of the resin finishing of cotton, in... 

Creep due to thermal deformation restricts thermoplastic-based composites from structural uses. However, creep in thermoplastic-based composites may be controlled through crosslinking chemical reactions or surface plasma modifications. 

Crosslinkers Chemical agents that form covalent bonds, linking one polymer with another. 

Petersen, H., Crosslinking chemicals and the chemical principles of the resin finishing of cotton, in Chemical Aftertreatment of Textiles, Mark, H., Wooding, N.S., and Atlas, S.M., Eds., Wiley Interscience, New York, 1971, pp. 135-233. 

Final mixingLaminar mixing of the deformable and flowable crosslinking chemicals into the highly viscous basic mixture. Distributive mixing must be superimposed on the laminar mixing. 

X index corresponding to crosslinking chemical bonds (and to entanglement of chains) h index corresponding to interchain physical bonds V volume of swollen sample, (Vj/V ),j( )2 = (yJ V. ... 

This is a long essay question which can be answered using any of the major modification techniques listed in the chapter on polyethylene modification. All information needed to compare and contrast two modification techniques, the changes in polyethylene physical and chemical properties, and an example of real world applications for that modified polyethylene are to be found for each ofthe techniques Sulphochlorination, Chlorination, Plasma Modification, Crosslinking - Chemical and E-Beam, and Graft Modification with Maleic Anhydride. 

There is a diversity of theroetical models used to elucidate the relationships between the molecular parameters of the network and the various experimental results [33-57]. Hence, the resulting deduction of the molecular structure of the network can depend on the model chosen for data analysis. Additionally, the structure of the networks at the supermolecular level is a function of the preparation conditions (temperature, concentration at crosslinking, chemical nature of the crosslinker, etc.). During network formation imperfections in the structure may also develop. In many cases the crosslinking process leads to fixation of otherwise nonequilibrium states. A wide variety of molecular superstructures may be produced within networks prepared from the same starting materials. This makes comparisons of experimental results from different literature sources extremely complicated. Consequently, a simple tabulation of previously published data is not particularly useful. 

While most of the materials considered herein are crosslinked chemically, several sections are devoted to physically crosslinked systems. This becomes all the more important when one notes that several recent patents and papers utilize the latter to synthesize IPN-like materials having a thermoplastic nature. 

The subscript A refers to the mode of crosslinking chemical or physical, as needed. 

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