COLLODION nitrocellulose solution

COLLODION Cellulose Nitrate Solution, Nitrocellulose Solution, Pyroxylin Solution, Box Toe Gum Flammable Liquid, II 2 3 3... 

Plastic films can be formed from a number of polymers two of the most common are collodion (nitrocellulose) and polyvinyl formal (Formvar). A number of other plastic materials can be used for thin films, some with specific advantages (101). Plastic films are usually prepared either by spreading a drop of solution of the plastic (in an appropriate solvent) onto a clean water surface, or by stripping off a film that has been coated onto a clean, flat surface (such as a glass slide) onto the surface of clean water. 

H. de Chardonnet obtained artificial silk by spinning a collodion (concentrated solution) of nitrocellulose. 

Sir Joseph Swan, as a result of his quest for carbon fiber for lamp filaments (2), learned how to denitrate nitrocellulose using ammonium sulfide. In 1885 he exhibited the first textiles made from this new artificial sHk, but with carbon fiber being his main theme he failed to foUow up on the textile possibihties. Meanwhile Count Hilaire de Chardoimet (3) was researching the nitrocellulose route and had perfected his first fibers and textiles in time for the Paris Exhibition in 1889. There he got the necessary financial backing for the first Chardoimet silk factory in Besancon in 1890. His process involved treating mulberry leaves with nitric and sulfuric acids to form cellulose nitrate which could be dissolved in ether and alcohol. This collodion solution could be extmded through holes in a spinneret into warm air where solvent evaporation led to the formation of soHd cellulose nitrate filaments. 

As shown by Mine [92], the reduction in viscosity of collodion cotton, nitrogen content 11.2%N, dissolved in acetone by ultra-violet irradiation is greater, the higher the concentration of nitrocellulose in the solution. 

The residue remaining insoluble in dilute acid may contain Insoluble salts, kiesHguhr, wood meal, etc. If nitrocellulose is present, the residue is shaken with ether-alcohol to determine the collodion. The ether-alcohol solution it allowed to settle, and an aliquot portion is withdrawn and evaporated. Gw wood meal errors due to this may be avoided by evaporating the acetone solution to 3(V2> c.c. and diluting with 100 c.c. of hot water, which precipitates the nitrocellulose. The residue is washed several times with the solvent and finally dried... 

The beginnings of microfiltration (MF) can be traced back into the 19th century with the synthesis of nitrocellulose in 1845 by Schoenbein. Fick then used ether-alcohol solutions of the same (collodion) to form the first nitrocellulose membranes in 1855. Even today, the most common polymers used in MF membranes are mixed esters of cellulose-including cellulose nitrate. 

The first plastics were actually developed during the last half of the 19th century. Paper is composed to a significant extent of the natural polymer cellulose and closely related substances. Treatment of paper with nitric acid produced the first (semi-) artificial polymer, nitrocellulose. Dissolution of nitrocellulose in alcohol/ether gave a viscous solution (collodion) which forms a hard film upon solvent evaporation. The polymer thus formed was quite flammable. An improved product based on nitrocellulose, termed celluloid, was molded into... 

Collodion syn. collodion cotton, a solution of nitrocellulose in ether or alcohol used as a solvent and to coat wounds. 

One hundred years after de Reaumur speculated about the production of artificial silk, the first practical solution capable of being spun was invented by a Swiss chemist named Schoenbein. In 1846, he invented guncotton (nitrocellulose) which, when dissolved in alcohol and ether, produced collodion, a thick, viscous solution. Another Swiss chemist, George Audemars, took out the first known patent [111] that was granted in 1855 for production of rayon in England. 

The verification of the alcohol commonly used in Menard s preparation came from several sources. Thorpe (36) describes celluloid as being made from a solution of nitrocellulose and camphor in ethanol. Celluloid was originally made from collodion and was only made from viscose rayon later in the twentieth century. In the Merck Index for 1989 (37), collodion is described as being... 

Plastics. In 1847 it was discovered that cellulose nitrate could be dissolved in a mixtin-e of ether and alcohol to produce a solution called collodion. Collodion is still in use today in pharmaceutical applications. Combination of nitrocellulose with castor oil and eventually camphor by Parkes (1862) and Hyatt (1870) led to the production of celluloid and ultimately the birth of the plastics industry. 

Plastic, carbon and metal films (Section 4.7) are used as specimen supports on TEM grids. There are two plastic support materials in use collodion, 0.5% solution of nitrocellulose in amyl acetate and formvar, 0.25% polyvinyl formal in ethylene dichloride. These polymers are available as powders, solutions or prepared films on TEM grids. Formvar films, especially holey ones, are used as substrates for the formation of holey carbon films. Today, collodion is not used too often, as it is not as stable in the electron beam as formvar or carbon films. 

While vulcanization of NR and GP was the first purposeful modification of natural polymers, the first man-made polymer was nitrocellulose, NC, discovered by Braconnot in 1833 (see Appendix I). Several commercial products followed, e.g., Collodion (lacquers based on alcohol-ether solution), Parkesine (the first thermoplastic material hot rolled and formable into variety of shapes), Ivorite (used as a substitute for ivory). Celluloid (camphor plasticized NC). Cellulose acetate, CA, was introduced in 1869 by Schutzenberger. Casein crosslinking by formaldehyde resulted in a 1885-patent hy Kritsche and Spitteler for what later became known as Galalith, a horn-like material quite successfully used even today as an imitation of ivory and porcelain [Seymour, 1982 1989]. 

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