Molecular weight dependent changes with time during latex film formation: a photon transmission study

✍ Scribed by Pekcan, Önder; Arda, Ertan

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 229 KB
• Volume: 47
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(1998100)47:2<231::aid-pi65>3.0.co;2-z

✦ Synopsis

A photon transmission method was used to probe the change with time of transparency during Ðlm formation from latex particles. Two di †erent latex Ðlms were prepared from high (HM) and low (LM) molecular weight poly(methyl methacrylate) (PMMA) particles, which were annealed at 10 min time intervals at various temperatures above the glass transition

The increase T g . in the transmitted photon intensity is attributed to the increase in "crossing I tr densityÏ at the junction surface. The back and forth activation energies (*E) were measured for HM and LM Ðlms and found to be around 29 kcal mol~1 and 53 kcal mol~1, respectively, for a reptating polymer chain across the junction surface. Monte Carlo simulations were performed for photon transmission through a rectangular lattice. The number of transmitted photons was calcu-N tr lated as a function of the mean free path of the photons. It was observed that N tr increased similarly to as the square of the mean free path of the photons I tr increased.

Society of Chemical Industry ( 1998