SYNOPSISThe surface compositions of a series of poly(pheny1ene ether)/nylon 6,6 blends (PPE/ PA), and PPE/HIPS blends, prepared by melt compounding and injection molding, have been quantitatively measured using XPS. For PPE/PA blends, the surface is dominated by the PA component for blends containing more than 25 wt % PA in the bulk. The enrichment of the PA component, which is actually the component of highest surface free energy, is rationalized in terms of the bulk morphology that consists of PPE domains in a PA continuous phase. Blends prepared by reactive extrusion processes, which form compatibilizing PPE/PA copolymers, show a decrease in surface PA enrichment with increasing copolymer content in the final blend. PPE/HIPS blends have a surface composition equal to the formulated value over the entire composition range, for both molded and solvent cast blends. The addition of 5% PVME to a 60/40 PPE/HIPS blend results in a molded surface containing 35-40 wt % PVME. 0 1992 John Wiley & Sons, Inc.

Static secondary ion mass spectroscopy (SSIMS) is applied to study the surface of the miscible polystyrene (PS)/ poly(viny1 methyl etherMPVME) blend. The blend surface is enriched with PVME and the enrichment is shown to depend on the composition and molecular weight of the blend constituents. A semi-quantitative analysis of SSIMS intensities to obtain surface compositions gives good qualitative agreement with previous x-ray photoelectron spectroscopy (XPS) results.

The surface compositions for a series of copoly(ether-esters) are determined from XPS and static SIMS measurements. The copolymers consist of a polybutylene terephthalate (PBT) hard block and a mixed soft block of two of the following polyethers-poly(propy1ene glycol) (PPG), poly(tetramethy1ene oxide (PTMO) and poly(ethy1ene oxide) (PEO). The surfaces of all the copolymers are enriched in the total polyether soft blocks. Quantification of XPS intensities shows the presence of both polyethers at the surface of these mixed soft-block copolymers, in relative amounts close to the bulk formulations. In the static SIMS measurements, direct observation of characteristic fragment ions related to the specific polyethers confirms their presence and relative abundance in the surface.

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The surface composition and morphology of a series of thermoplastic elastomers based on polyester (PBT)–polyether (PPG) copolymers have been studied using x-ray photospectroscopy (XPS) and static secondary-ion-mass spectroscopy (SIMS). In all cases, an enrichment of the polyether soft block at the surface is observed. The degree of preferential surface adsorption is greater for molded specimens compared ot the solvent cast films. The enrichment factor (surface content/bulk content) is greater for speciment of highest PBT content. Angle-dependent XPS measurements are fit with an enriched overlayer model and a continuous profile model. Static SIMS measurements are consistent with the XPS results for molded versus solvent cast films, but indicate that some PBT is present at the outer surface of all specimens analyzed.