Chlorine content, char

Cotton with flame-retardant property was made by grafting with acrylamide and his-(heta-chloroethyl) vinylphosphonate, and subsequent treatment with stannic chloride. Thermal decomposition behaviors of unmodified and modified samples were studied under nitrogen atmosphere at 500 C. It was found that carbamoylethyl- and carboxyethylation, grafting and stannic chloride treatment increased the yield of char residue and water, but decreased that of tar. In flame-retardant cotton, the temperature of thermal decomposition onset and completion were lower than those in unmodified cotton. And the rate of thermal decomposition was slower than that in unmodified cotton. Phosphorus content in char residue did not change by thermal decomposition. But chlorine content introduced by grafting decreased by thermal decomposition. 

Phosphorus and Chlorine Contents. Phosphorus and chlorine contents of the samples in char residue at kOO C are shown in Table IV. Phosphorus content did not change by thermal decomposition in all samples. But chlorine content decreased by pyrolysis. Chlorine introduced by stannic chloride treatment hardly decreased, but that by grafting decreased easily by pyrolysis. Stannic chloride is not introduced in cotton in the form of stannic chloride, because the chlorine content of stannic chloride treated cellulose is very lower than that calculated from weight increase. X-ray diffraction trace of burned sample... 

Most of the particular difficulties of straw gasification are caused by the high K and Cl-content. The behaviour of these impurities in the successive process steps is therefore of special importance. The selection of a method for their removal is a major process decision. Chlorine volatilisation starts at relatively low pyrolysis temperatures of about 200 C. About half of the chlorine can be removed into the pyrolysis gas up to about 500°C. The rest of the HCl is volatilised together with the potassium at higher temperatures. At lower pyrolysis temperature, K can be kept completely within the char particles together with the residual ash, but the chlorine distributes between char and gas. 

The very signifieant smoke suppression effect of the FeOOH in the blends is explained in terms of iron/chlorine compounds formed in situ. The maximum smoke suppression effect was obtained at a blend ehlorine content of about 20%. It was also shown that the char formation is directly related to smoke formation and suppression in these polymer blends. 

There is a very high correlation (r = 0.99) between char formation and percentage of chlorine in the blend. This suggests that it is the PVC content of the blend which influences the char-forming crosslinking reactions. Across the range of ABS/PVC iron-free blends studied, even... 

Properties Light amber clear Iiq, mild char, odor sol, in alcohols, glycols, glycol ethers, aliphatic and chlorinated hydrocarbons water-disp. sp.gr. 0.950 0.01 dens. 7.9 Ib/gal vise. 1200 cps min, acid no, 12-16 alkali no. 120-140 flash pt. (OC) > 170 C pH 9.9 0.5 (10% disp,) 100% active 60% min. amide content Schercomid OME [Lubrizoi Advanced Materials]... 

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