Fluorocarbon Compounds

Certain fluorocarbon processing aids are known to partially alleviate melt defects in extrudable thermoplastic hydrocarbon polymers and allow for faster, more efficient extrusion. Blatz first described the use of fluorocarbon polymer process aids with melt extrudable hydrocarbon polymers wherein the fluorinated polymers are homopolymers and copolymers of fluorinated olefins having an atomic fluorine to carbon ratio of at least 1 2, wherein the fluorocarbon polymers have melt flow characteristics similar to that of the hydrocarbon polymers (4). 

Vinylidene fluoride homopolymers can be used to improve the extrusion of low density poly(ethylene) (5). 

Multimodal fluoropolymers are superior in performance than unimodal fluoroplastics when used as polymer processing additive (6). 

---

In the absence of air, TEE disproportionates violently to give carbon and carbon tetrafluoride the same amount of energy is generated as in black powder explosions. This type of decomposition is initiated thermally and equipment hot spots must be avoided. The flammability limits of TEE are 14—43% it bums when mixed with air and forms explosive mixtures with air and oxygen. It can be stored in steel cylinders under controlled conditions inhibited with a suitable stabilizer. The oxygen content of the vapor phase should not exceed 10 ppm. Although TEE is nontoxic, it may be contaminated by highly toxic fluorocarbon compounds. 

However, fluorocarbon compounds might be of considerable interest for LB-layer fabrication. Their dielectric and mechanical characteristics and thermal and chemical stability are not inferior to those of polyimides, and highly developed synthesis technology makes it possible to create systems with various predictable properties. Such films have been found to demonstrate a high degree of perfection and excellent dielectric characteristics.69,70... 

DuPont. Solubility Relationships of the Freon Fluorocarbon Compounds, Technical Bulletin B-7, (Wilmington. DE DuPont de Nemours, 1966). 

FLUOROCARBONS. Compounds of carbon and fluorine-analogs of hydrocarbons in which the hydrogen has been replaced by fluorine. 

It has been determined using ll,FNMR that some of the perfluoro ethers and other per-fluorocarbon compounds synthesized with this process have residual hydrogen remaining on the organic compound in concentrations below 3 parts per billion. To put that in perspective, in polytetrafluoroethylcne which is made from tctrafluorocthcne monomer, the hydrogen content is several parts per million. 

Phase-separated monolayers and liposomes were characterized by R. Elbert1011 who synthesized saturated and polymerizable fluorocarbon amphiphiles (59, 60, 61) and investigated their mixing behavior with CH2-analogues and natural lipids. In these systems the fluorocarbon compounds are incompatible with hydrocarbon lipids in a wide range of compositions and tend to form domains of pure fluorocarbon and hydrocarbon amphiphiles. The domains can be visualized by freeze-fracture electron microscopy. 

Fluorination of normal hydrocarbons is not difficult with the La-Mar fluorination process however, fluorination studies also have been successful with structurally unusual hydrocarbon compounds (65-67a) (see Fig. 13). These studies were undertaken to establish that direct fluorination was useful even with some of the most sensitive hydrocarbon structures. While the initial studies of the successful direct fluorination of these species often resulted in yields as low as 10%, these same experiments, after additional technical developments in our laboratory, routinely give yields of 70—95%. Such syntheses have often been repeated in our laboratories to satisfy scientific needs for such compounds in other laboratories. The sterically crowded fluorocarbon compounds prepared in... 

The fluorocarbons trichlorofluoromethane, dichlorodifluoromethane, and chlorodifluoromethane are major fluorocarbon compounds. 

Even from the foregoing cmde but useful generalisations, it will be appreciated how unusual the chemistry of fluorocarbon compounds is. 

The theoretical study of incendiary reactions has been aided by the use of com.puter programs for the study of the equil products (Refs 15 41), as well as for the prediction of the adiabatic reaction temps. An example of the complexity of the reaction products of a fluorocarbon, compounded with 5% epoxy binder, is given by Tanner (Ref 80). It will be observed, that only the carbon remains as solid product, and that the effect of the fluorine is one of increasing the fraction of gaseous products, as well as to provide the thermal energy (see Table 8)... 

Fluorocarbon compounds are lipid soluble and, thus, generally well absorbed through the lung. Absorption after ingestion is much lower than after inhalation. Most of the fluorinated hydrocarbons are immediately absorbed. 

Figure 16.2 Fluorous small-molecule microarrays. Small-molecule histone deacetylase (FiDAC) binders are noncovalently immobilized onto a glass slide coated with fluorocarbon compounds. An antibody labeled with a fluorescent dye recognizes HDAC proteins. See color plate 16.2.

Before fluorocarbon compounds were discovered by Thomas Midgley in 1928 and introduced by Du Pont to the refrigeration market in the 1930 s, refrigerants then in use were either quite... 

Fluorocarbon compounds were radiolyzed to establish the existence and assess the role of valence tautomers in radiation chemistry. Dewar-octafluorotoluene and -decafluo-roxylene have been isolated and identified as products of the photolysis and radiolysis of their respective aromatic parent in condensed phase. Dewar hexafluorobenzene was irradiated to 10 Mrad doses and found to revert to its KekulS isomer with a G-value of 10, to polymerize with G 20, and, in addition, to give rise to a new isomer. The concept of an energy sink is introduced whereby part of the energy absorbed by an aromatic system is stored in the form of interconvertible valence isomers which react further to yield polymers or decay to the ground state. 

A. Nakahara, T. Sata, M. Shirozu and K. Kunai, Preparation method of fluorocarbon compounds having carboxylic acid groups, Jpn. Pat. JP 62-12921 (examined application). 

Fluorocarbons - Compounds consisting solely of fluorine and carbon. [5]... 

General organic compounds Relative response Fluorocarbon compounds Relative response... 

Fluorocarbon Compound Oxygen Solubility ml/IOOmI 25 Vapor Pressure mmHg 37.5 °C Boiling Point c Density gm/ml 25 C Surface Tension dynes/cm 25 C... 

---