Yet a quantitative description of segment length distribution at the surface of a multicomponent polymer remains elusive since fundamentally polymers involve a distribution of chain lengths which yield the particular properties it would be desirable to know whether at the surface the distribution of segment or chain lengths is different than in the bulk therefore like composition the . Surface morphology and end group distributions of the ba c8 polymer films a d freshly prepared films a b and c are afm height images d e and f are tof sims br ion images b e after . Introduction mass spectra of secondary ions emitted from polymer surfaces by bombardment with primary ions supply information on the chemical structure and composition of the polymer and under certain conditions on the molecular weight distribution the spectra can also be used to investigate modifications of polymers produced by the impacting primary ion itself or by prior ion irradiation . It was found that the distribution of pdms segment lengths segregated at the surface of the thick film was almost identical with that in the bulk for pu dms with pdms nominal molecular weight of ca 1000 da these results allow the development of an analysis of ion structure and a stepwise procedure for evaluating the segment length distributions in the near surface region of siloxanes. This article reviews the recent applications of time of flight secondary ion mass spectrometry in the determination of surface structures of semicrystralline and amorphous polymer films examples given include the determination of end group
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