Патент USA US2404267код для вставки
Patented July is, 1946 2,404,267 \ UNITED STATES PATENT ‘OFFICE METHACRYLIC ESTERS AND COPOLYMERS THEREOF Carl ,E. Barnes, Acton, Masa, assignor to Polaroid , _ Corporation, Dover, Del., a corporation of Del aware No Drawing. Application February 20, 1942, Serial No. 431,732 1 Claim. (Cl. 260-486‘) 1 , This invention relates to a new and improved synthetic'resin and more'particularly to alpha (o-chlorophenyl) ethyl methacrylate. An object of the invention is to provide such ' a resin which is useful in the formation of hard, transparent, optical elements possessing relative ly high indices of refraction. Further objects of the invention are to provide a polymerized resin of the character described 2 copper cloth was added to the mixture as an in hibitor of polymerization. The mixture was then permitted to stand at a temperature of from 50 to 60 degrees C. for several hours and was dilut ed with ether and extracted several times with dilute sulphuric acid. It was then washed sev eral times with dilute sodium hydroxide and il nally with water. The ether layer was then con centrated and distilled under reduced pressure, and tow provide a copolymer of a resin of the 10 alpha (o-chlorophenyl) ethyl methacrylate being character described with a. resin from the class distilled o?. consisting of the unsaturated methylene com Monomeric alpha (o-chlorophenyl) ethyl pounds, and more speci?cally to provide a co methacrylate is a liquid with a boiling point of polymer of a resin of the character described approximately 146 degrees C. at 11 mm. pressure. with a methacryiate resin. 15 In polymerizing the monomer, either alone or Other objects of the invention will in part be obvious and will in part appear hereinafter. coniointly with a resin from the class consisting of the unsaturated methylene compounds, poiy- . There is a pressing demand for a synthetic merization is preferably commenced at a tem resin composition which may be used in the for perature of from about 60 to 65 degrees 0., and mation of optical elements such for example, as 20 the temperature is preferably raised before poly lenses, prisms, and the like and which may pref _merization is completed to approximately 130 erably be cast or molded to the desired form. A degrees C. r ' . preferred resin is one which may be cast into the The polymeric valpha (o-chlorophenyi) ethyl desired form by, for example, polymerizing the methacrylate has a density at 20 degrees C. of monomer in a suitable mold or by advancing the 25 "1.269. It has an index of refraction MD”) of polymerization of the partially polymerized ma 1.562 and a reciprocal dispersion of 37.5, It is terial in a suitable mold. This invention contem substantially colorless, hard, brittle and trans plates the provision of new synthetic resins or parent. plastics which are particularly useful in the pro It will be noted that the refractive index of duction of products of the character described. 30 the polymer of alpha (o-chlorophenyl) ethyl More speci?cally, this invention contemplates methacrylate is above 1.55, which is a preferred the provision of synthetic resins which, when‘ condition. The polymer is, however, somewhat polymerized, give a transparent, hard, substan brittle, and-where it is to be employed under con ' tially colorless product having a relatively high ditions such that it may be subjected to shock, it index of refraction and which is suitable for use 35 may be desirable to combine it with plastics in the production of optical elements of the whose polymers are somewhat tougher. This is character described. The compositions of the present invention comprise resins from the class consisting of al ~ especially true where the high refractive index is not required. In this connection it should be noted that alpha (o-chiorophenyl) ethyl meth pha (o-chlorophenyl) ethyl methacrylate and 40 acrylate may satisfactorily be copolymerized with copolymers thereof with other resins from the virtually all the polymerizable ‘unsaturated class consisting of the unsaturated methylene methylene compounds to produce products hav compounds. - Alpha (o-chlorophenyl) ethyl methacrylate ing diverse and varied physical and optical prop erties. Suitable compounds for use in forming may be prepared in the following manner, which 45 copolymers of the type described with alpha is given as illustrative of one method of prepar (o-chlorophenyl) ethyl methacrylate are methyl ing the material. A suitable quantity of o-chlo methacrylate, ethyl methacrylate, isopropyl' rophenyl methyl carbinol having a boiling point of 123 degrees C. at 18 mm. pressure was pre methacrylate, ter-butyl methacrylate, cyclohexyl methacrylate and other esters of alpha-metha pared from o-chlorobenzaldehyde and methyl 50 crylic acid: the vinyl esters such as vinyl formatc, magnesium bromide in ways known to the art. vinyl acetate, vinyl propionate and the vinyl 156.5 grams (1 mol) of ‘o-chlorophenyl methyl ester of chloracetic acid, etc; the vinyl ketones carbinol was mixed in a suitable ?ask with 154 such as methyl vinyl ketone; styrene; furylethyl grams (1 moi) of methacrylic anhydride and 79 ene (vinyl furane). Other suitable materials for grams (1 mol) of pyridine. A small amount of use in the formation of copolymers falling with 2,404,267 in the scope of this invention‘ are the esters of itaconic acid, the esters of acrylic acid, and the vPolymerization of the products of this inven tion may be accomplished preferably by heating esters of methylene malonic acid. _ mixtures of monomers or the slightly polymerized It is to be understood that the list of substances materials at relatively low temperatures, or Just given is not all-inclusivealthough it is believed a. above the melting point of the monomer, until that the materials mentioned constitute the pre a hard product is obtained, when polymerization ferred substances for use in the present inven may be carried forward to a desired point at sub tion. - i It is also to be understood that, if desired, stantially increased temperatures. Higher tem peratures of polymerization generally increase hardening agents may be employed in small or 10 the brittleness of the product. It is, of course, substantial percentages. Any of a vast number to be understood that where molded optical ele 'of suitable hardening agents may be used; A ments are to be produced, the surfaces of the preferred hardening agent for use with copoly mold should be optically smooth as the molded mers comprising methyl methacrylate is either product will have substantially the surface prop methacrylic acid or acrylic acid, although other 15 erties of the mold. ' known hardening agents such as methacrylic an Since certain changes may be made in the hydride or allyl methacrylate may be used suc above article and different embodiments of the cessfully. invention could be made without departing from While a preferred product is one which is its scope, it is intended that all matter contained transparent and which may be molded during 20 in the above description shall be interpreted as polymerization into a suitable optical element, illustrative and not in a limiting sense. it is to be understood that products which are It is also to be understood that'the following translucent or even opaque and hence useless in claims are intended to cover all of the generic the formation of optical elements may be sat and speci?c features of the invention herein de scribed and all statements of the scope of the in vention which, as a matter of language, might be said to fall therebetween. ‘ isfactorily employed for other purposes where particularly hard, readily molded, polymerized plastics are desirable, and such products com prising alpha (o-chloropheny'l) ethyl methacry late or a copolymer thereof with an unsaturated methylene compound are to be deemed to fall 30 within the scope or this invention. What is claimed is: Alpha (o-chlorophenyl) ethyl methacrylate. CARL E. BARNES.