US 5,631,329 A · Process for producing hyper-comb-branched polymers

Abstract

The specification discloses a process for producing poly-branched polymer having relatively high molecular weight by forming a first set of branches by polymerizing monomers which are either protected against or are non-reactive to branching and grafting during polymerization, grafting that first set of branches to a core having a plurality of reactive sites capable of reacting with the reactive end units of said branches, either deprotecting or activating a plurality of monomeric units on each of said branches to create branch reactive sites, forming a second set of branches in the same manner as the first set of branches were formed, grafting the second set of branches to the first set of branches by reacting the reactive end units of the second set of branches with each said branch reactive site on said first set of branches and repeating the foregoing steps reiteratively to form and attach subsequent sets of branches to prior branch sets until a desired number of iterations has been effected.

Claims66

Dependent claims

A process for producing non-crosslinked poly-branched polymers having the general formula ##STR18## wherein:

C is a core molecule;
each {(A)-(B)} branch is a linear polymer or copolymer chain;
each R is the residual moiety of an initiator;
A and B are polymerizable monomers or comonomers capable of withstanding the conditions required for branching therefrom or grafting thereto, at least during the polymerization of the {(A)-(B)} linear polymer chain and during its grafting to a prior {(A)-(B)} branch;
each G is a grafting component, and the designation ##STR19## indicates that G can extend from either an (A) unit or a (B) unit;
n is the degree of polymerization of the indicated generation comb branches, y is the fraction of B units in the indicated generation branch, and has a value of 0.01 to 1;
the superscripts 0, 1 and i designate the comb-branch generation level, with i beginning at "2" and continuing for the number of reiterative branch set generations in the polymer;
and at least n.sup.0 and n.sup.1 are .gtoreq.2;
said process comprising
(I) forming a core having at least one reactive site;
(II) reacting essentially all of the reactive sites of said core with a reactive polymer having the unit formula ##STR20## to form multiple branches which contain reactive (B.sup.0 ) sites on each branch, using a reactive scheme such that the reactive monomer units (B.sup.0) are capable of withstanding the conditions required for branching therefrom or grafting thereto to ensure that said reactive polymer ##STR21## reacts with said reactive sites of said core, but that no reactions occur at said (B.sup.0) sites;
(lII) repeating step (II) sequentially by reacting reactive polymer having the unit formula ##STR22## with the reactive sites of said polymerizable B.sup.(i-1) monomers or comonomers of the previous generation to form successive generation of branches to give the desired non-crosslinked poly-branched polymer.

9 more elements

A process for producing a poly-branched polymer having a relatively high molecular weight in a relatively low number of iterations, said process comprising:

(a) forming a first set of branches by initiating polymerization of a first set of monomers which are either protected against or non-reactive to branching and grafting during said polymerization, wherein each of said branches has (i) a degree of polymerization of at least about 50, (ii) a reactive end unit upon completion of said polymerization, and (iii) said reactive end units being incapable of reacting with each other;
(b) grafting said branches to a core having a plurality of core reactive sites capable of reacting with said reacting end units of said branches, wherein said grafting step is performed utilizing a grafting ratio of from about 0.8 to about 1.2 reactive end units per core reactive sites, and wherein said grafting step is also performed in the presence of a proton scavenger, said scavenger being present in a concentration of at least about 1 equivalent of scavenger for every reactive end unit, and wherein said grafting step is performed in a time period of less than about 1 hour;
(c) either deprotecting or activating a plurality of monomeric units on each of said branches to create branch reactive sites;
(d) forming a second set of branches by repeating step (a) above with a second set of monomers;
(e) attaching said second set of branches to said first set of branches by reacting said reactive end units of said second set of branches with said branch reactive sites on said first set of branches, and thereby form said poly-branched polymer;
and
(f) performing at least one of the following steps:
(i) ensuring that NaOH or other salts are removed from at least one of said first set of branches, said second set of branches, and said poly-branched polymer, and (ii) ensuring that said poly-branched polymer is dried at temperatures less than about 60.degree. C.

5 more elements

Dependencies are inferred from the claim text.

Process for producing hyper-comb-branched polymers

Life of this patent

Process for producing hyper-comb-branched polymers

Life of this patent

Abstract

Claims66