Structural Studies of Novel Siloxysilsesquioxanes

Abstract

Five silsesquioxanes (RSiO3/2)2n with R = siloxy and n = 4, 5 have been investigated by X‐ray crystallography, MALDI‐TOF mass spectrometry, and differential scanning calorimetry (DSC).

New Monofunctional POSS and Its Utilization as Dewetting Additive in Methacrylate Based Free-Standing Films

“…They can be indexed with hexagonal unit cells as are many other POSS related compounds. 30, [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55] Results are reported in Table 2. As noted by Fu et al, 54 corner substitution has little effect on the crystal structure.…”

Synthesis and structure of functional spherosilicate building block molecules for materials synthesis

“…These compounds are interesting from both application and fundamental perspectives. They are useful in a broad range of areas including atomic scavengers, cores for branched dendritic macromolecules, molecular composite materials, optical fibers and cosmetics [2][3][4][5][6]. They are structurally important because the cubic Si 8 O 12 and the pentagonal prismatic Si 10 O 15 cages contain double four ring (D4R) and double five ring (D5R) units, respectively.…”

“…Attempts to model this as two distinct atoms were not successful. The occupation of the two components in both cases was modeled by a standard floating occupancy free variable and was found to be approximately 1:1 for the case of Ti(1) and approximately 3:1 for the case of Ti (2).…”

“…Three of the four molecules are Lewis base adducts with tin and the fourth water is hydrogen bonded to an exocage oxygen belonging to the silicate molecule. The two pentagonal faces making up the spherosilicate cage are not symmetrical due to ''puckering'' of corresponding Si-O-Si edges of the two opposite faces, similar to what is observed in other Si 10 O 15 containing structures [2,51,59].…”

ESI and MALDI mass spectrometry of large POSS oligomers

“…There are to date only a few papers reporting mass spectra of POSS polymers and oligomers [15][16][17][18][19][20][21][22][23]. These studies all investigate systems, and especially synthetic intermediates, in which there are a large number of -OH groups.…”