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US 4,831,109 AGranted
Copolymerizable UV stabilizers
AssigneeMinnesota Mining and Manufacturing Company
InventorsSumita B. Mitra, Smarajit Mitra
Life of this patent
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Abstract
This invention describes UV-stabilized step growth polymers such as polyesters, polyurethanes, polycarbonates, and combination thereof. The UV-stabilizing moieties present in these polymers comprise chemically bound, pendant ortho-hydroxydiphenyl ketone based moieties. The polymers are especially useful as protective films and fibers which are highly resistant to ultraviolet (UV) and sunlight degradation.
Claims17
A polymer having the formula
- wherein R.sup.1 and R.sup.2 are the same or different and each is selected from the group consisting of hydrogen alkoxyalkyl, aryl, aryloxyalkyl, alkoxyaryl, alkyl, aralkyl, and alkaryl groups, or R.sup.1 and R.sup.2 together can form an aliphatic cyclic structure of 5 to 7 atoms which include carbon and zero to two non-connected oxygen atoms, wherein R.sup.1 and R.sup.2 together total from zero to forty carbon atoms;
- x is an integer from 0 to 20, y is 0 or 1, provided that both x and y are not zero;
- m is 0 or 1;
- A and B are the same or different and represent zero to eight monovalent substitutents on the aromatic rings selected from the group consisting of (1) hydrogen, halogen, nitro, tertiary amino, amido, and cyano, and (2) alkyl, alkenyl, aryl, aralkyl, alkaryl, alkoxy, aryloxy, aralkyloxy, alkaryloxy, aryloxyalkyl, and thioalkyl, these groups having 1 to 20 carbon atoms and up to 6 non-connected oxygen and sulfur atoms;
- or A and B can be linked to said aromatic rings by a divalent keto, sulfoxide, and sulfone group, with the proviso that when m=0, W is not present, and then a benzophenone structure is present, and when m=1, then W is a single bond or a divalent group;
- ##STR18## in which R.sup.3 is an alkyl, alkoxyalkyl, aryl, aryloxyalkyl, alkoxyaryl, aralkyl, or alkaryl group;
- and R.sup.4 and R.sup.5 independently are the same as R.sup.1 and R.sup.2 which are defined above;
- R is any divalent organic group having 1 to 20 carbon atoms;
- D is ##STR19## wherein R is as previously defined;
- P is at least one and q is zero or greater than zero, and when q is greater than zero the ratio of q to p is in the range of 1:10,000 to 10,000 to 1;
- and the number average molecular weight of the polymer is in the range of 1,000 to 10,000,000.
8 more elements
A method for preparing a polymer comprising in sequence the steps:
- (a) reacting, with an acid catalyst, a trihydroxy compound having the formula ##STR20## with an aldehyde or ketone ##STR21## to provide a cyclic acetal or ketal having the formula ##STR22## wherein R.sup.1 and R.sup.2 are the same or different and each is selected from the group consisting of hydrogen, and alkyl, alkoxyalkyl, aryl, aryloxyalkyl, alkoxyaryl, aralkyl, and alkaryl groups, or R.sup.1 and R.sup.2 together can form an aliphatic cyclic structure of 5 to 7 atoms which include carbon and zero to two non-connected oxygen atoms, wherein R.sup.1 and R.sup.2 together total from zero to forty carbon atoms;
- x is an integer from 0 to 20,
- y is 0 or 1, provided that both x and y are not zero;
- R.sup.6 and R.sup.7 are H, alkyl, aryl, or alkaryl, alkoxyalkyl, aryloxyalkyl, alkoxyaryl, or alkaryl groups, or R.sup.6 and R.sup.7 taken together can form an aliphatic cyclic structure having 5 to 7 carbon atoms and up to 2 non-connected oxygen atoms,
- (b) reacting said resulting cyclic acetal or ketal with a leaving-group-containing compound to provide a leaving-group-containing cyclic acetal or ketal having the formula ##STR23## wherein R.sup.1, R.sup.2, x and y are as previously defined and z is a leaving group,
- (c) reacting said resulting leaving-group containing cyclic acetal or ketal with a 2,4-dihydroxybenzophenone based compound to provide a 4-alkoxy-2-hydroxybenzophenone derivative of the formula ##STR24## wherein m is 0 or 1, x and y are as previously defined, and W is a single bond or a divalent group ##STR25## in which R.sup.3 is an alkyl, alkoxyalkyl, aryl, aryloxyalkyl, alkoxyaryl, aralkyl, or alkaryl group;
- and R.sup.4 and R.sup.5 independently are the same as R.sup.1 and R.sup.2 which are as previously defined, and
- (d) subjecting said resultant 4-alkoxy-2-hydroxybenzophenone based compound to acid hydrolysis to provide said monomer having the formula ##STR26## wherein R.sup.1, R.sup.2, A, B, W, x, y, and m are as previously defined, and
- (e) condensing said monomer with at least one multifunctional monomer containing acid, acid anhydride, acid chloride, ester, chloroformate, or isocyanate functionality, or with phosgene to provide a random polymer having the formula ##STR27## wherein R.sup.1, R.sup.2, A, B, W, x, y, and m are as previously defined, and
- R is any divalent organic group having 1 to 20 carbon atoms,
- D is ##STR28## p is at least one, q is zero or greater than zero, and when q is greater than zero, the ratio of q to p is in the range of 1:10,000 to 10,000 to 1, and said polymer has a number average molecular weight in the range of 1,000 to 10,000,000.
8 more elements
Dependencies are inferred from the claim text.