Silicones grease

It is often advisable to lubricate ground-glass joint surfaces with an extremely thin film of vaseline. This applies particularly to joints employed in assemblies for distillation under reduced pressure. For distillations under greatly reduced pressures or at very high temperatures it is essential to employ a special lubricant, e.g., silicone grease. 

The disc contains a hole, centrally placed, through which a small glass stirrer can be pushed. The stirrer should be smeared with a very small amount of silicone grease where it passes through the spring disc. A relatively powerful motor is required for this apparatus. 

In filling the tube R, one tap is inserted after being carefully greased with a high-vacuum or silicone grease. The taps are provided with scored grooves (that run completely around them near their outer end) which act as a trap to prevent... 

Pyrazolines Imidazoles Thiazoles Oxadiazoles 1 -Phenylpyrazoles Purines Dioxolanes Ox azolines 10% Cyanethylated mannite on Celite 545. 5% OV-17 on Chromosorb W, AW-DMCS (H.P.). Carbowax 4000, dioleate on firebrick, 190 °C. Silicone grease on Chromosorb P. Apiezon L on firebrick C-22, 220 °C. 15% Hallcomid M-18 on firebrick. Carbowax 20M on Gas-Chrom P. Ethyleneglycol succinate on Diatoport-S. 

Silicone greases do, however, have uses in extrusion for coating dies etc., to facilitate stripping down. Greases have also found uses in the laboratory for lubricating stop cocks and for high-vacuum work. 

If we add a known amount of a compound to our solution, we can use it to quantify the material of interest. This is great except that we may not want to contaminate our material with some other compound. A number of people have looked at using standards that are volatile so that they can be got rid of later (TMS is an example that we have seen published). The problem with this approach is that if the sample is volatile then you need to run it quickly before it disappears. TMS disappears really quickly from DMSO so it is probably not a good idea in this case. TMS also suffers from the fact that it has a long relaxation time so you have to be very careful with your experiment to ensure that you do not saturate the signal. The last major problem with TMS is that it comes at the same part of the spectrum as silicon grease which can be present in samples. Choosing a standard so that it has a short relaxation time, is volatile and comes in a part of the spectrum free of interference is really tricky. In fact, we wouldn t recommend it at all. 

As it reacts explosively in bulk, the amount of silicone grease used on joints must be minimal. 

Adhesion of, e.g., paint on polymeric materials such as in automotive bumper material may be poor because of silicon grease being present at the surface as a result of handling the bumper before applying the paint. By using ESCA such problems can be tackled easily and customer complaints can be refuted or accepted. 

In this microcalorimeter, the heat sink is not a massive metal block but is divided into several parts which are mobile with respect to each other. Each thermoelectric element (E) and a cell guide (D) are affixed to a fluxmeter holder (C). The holder (C) is mobile with respect to a massive arm (B) which, in turn, rotates around a vertical axle (A). All parts of the heat sink are made of brass. Surfaces in contact are lubricated by silicone grease. Four thermoelectric elements (E) are mounted in this fashion. They enclose two parallelepipedic calorimetric cells, which can be made of glass (cells for the spectrography of liquids are particularly convenient) or of metal (in this case, the electrical insulation is provided by a very thin sheet of mica). The thermoelectric elements surrounding both cells are connected differentially, the Petit microcalorimeter being thus a twin differential calorimeter. 

Whenever apparatus with ground glass joints is used, Dow silicone grease provides excellent lubrication and airtight seal. 

ALKYLHALOSILANES, ALKYLSILANES HALOSILANES, ORGANOSILYL PERCHLORATES SILANES, SILICONE GREASE, SILICONE LIQUID, SILICONE OIL SILYLHYDRAZINES, TRIALKYLSILYLOXY ORGANOLEAD DERIVATIVES... 

The main source of human exposure to cyclic siloxanes is PCPs. Other less significant sources are rubber products, sealants, cookware, silicone grease, pharmaceuticals, medical devices, electronics, dust, and even indoor and outdoor air [277, 281]. The highest concentrations of cyclic siloxanes reported by Lu et al. [282] in PCPs from China were 72.9 pg/g D4 and 1,110 pg/g D5 in shampoos and... 

ESCA was employed to analyze membranes before and after use in the desalination cell. Wide scan ESCA spectra were obtained on the last two membranes listed in Table VII. Table IX lists the binding energies (B.E.) and the atomic fractions (A.F.) for the membranes studied. In addition to the expected carbon, oxygen, sodium, and sulfur peaks, two small peaks were attributed to nitrogen and silicon, which may be due to the contamination in the air (silicon grease). A smaller photo peak was observed at 51.3 eV and remains unasslgned. Overall, there is no significant surface contamination of the membranes. 

A paste made from a 1 1 mixture of mineral oil and silicone grease is used to lubricate the stirrer. 

---