Polymers with pendant olefinic

The incorporation of cyclic olefins into the photoresist polymer backbone, it must be noted, represents a radical departure from the conventional 193-nm photoresist design concept, as typified by acrylate polymers or acrylate polymers with pendant cyclic olefins, or cyclic olefin/acrylate hybrid polymers. It is the unique architectures of the polymer backbones of these resist materials that impart properties (such as high etch resistance, low UV absorption at 193 nm, etc.) that make them very good candidates for 193-nm resist applications. 

Ionic polymers are a special class of polymeric materials having a hydrocarbon backbone containing pendant acid groups. These are then neutralized partially or fully to form salts. lonomeric TPEs are a class of ionic polymers in which properties of vulcanized rubber are combined with the ease of processing of thermoplastics. These polymers contain up to 10 mol% of ionic group. These ionomeric TPEs are typically prepared by copolymerization of a functionalized monomer with an olefinic unsamrated monomer or direct functionalization of a preformed polymer [68-71]. The methods of preparation of various ionomeric TPEs are discussed below. 

Polymeric polyolefins, such as polybutadiene, secondary amines, and synthesis gas, are reacted in the presence of a catalyst system comprising a ruthenium-containing compound, a rhodium-containing compound, a steri-cally hindered phosphine, and a solvent [1191]. Preferred polybutadiene feedstocks are those with a predominance of main chain, rather than pendant olefin groups and in particular, those polymers containing both the 1,2-polybutadiene and 1,4-polybutadiene units. These polymers of high amine content are useful as down-hole corrosion inhibitors. 

Employing a molar excess of the alkyne over the active hydrogen of only 12 percent the selectivity (determined by proton NMR after work-up) may be expressed as the ratio of Si-C=CH- to Si-CH2-CH2-CO-, which is about 100 1 [16]. The same reaction, carried out with silicone polymers with 10 or more pendant silicon-bonded hydrogen atoms, proceeds similarly cleanly without noticeable crosslinking by acrylic hydrosilylation. A slight excess of triple bond over Si-H groups is mandatory to suppress this side reaction as well as hydrosilylation of the olefinic group of the 2-silylalkene isomer product (see Table 2.). 

An alternative method for the preparation of polymer-chained pendant ligands has been recently developed.102 The polymerization of the (R)-hydroxylpiperidinyl fragment was realized by ROMP of a bicyclic olefin with the commercially available Grubbs catalyst. 

Terpolymers made from two different olefins and CO are known. They were first described in Brubaker s initial patent and involved the free radical initiated terpolymerization of CO and C2H with another olefin such as propylene, isobutylene, butadiene, vinyl acetate, diethyl maleate or tetrafluoroethylene More recently, in another patent, Hammer has described the free radical initiated terpolymerization of CO and C2H with vinyl esters, vinyl ethers or methyl methacrylate 26Reaction temperatures of 180-200 °C and a combined pressure of 186 MPa were employed. Typically a CO QH4 olefin molar ratio of 10 65 25 was observed in the terpolymers. In other patents, Hammer 27,28) has described the formation of copolymers with pendant epoxy groups by the free radical initiated polymerization of CO, QH4, vinyl acetate and glycidyl methacrylate. Reaction conditions similar to those stated above were employed, and a typical CO C2H vinyl acetate glycidyl methacrylate molar ratio of 10 65 20 5 was observed in the product polymer. 

Usually the Zigler-Natta co-ordination initiator system is used to graft oc-olefins onto other polymers to give stereo block/graft copolymers, which contain isotactic/atactic sequences. In the Zigler-Natta co-ordination catalyst [69] system, the diethyl aluminium hydride reacts with pendant groups to form macromolecular trialkyl aluminium. The residual initiator is freed by extraction methods. 

A number of researchers have heterogenized olefin metathesis active complexes in polymers containing pendant vinyl groups via different methodologies. Barrett and coworkers formed (278) via reaction of (3a) with a lightly cross-linked solvent swellable vinylated polystyrene or Merrifield resin to form a bead-snpported catalyst that conld be directly compared to their previonsly reported similarly supported (2a) (279) (Scheme 24). Results from this study are described in Table 12. 

Coordination polymerization of dienes has progressed significantly within the last decade. Selective polymerization of 1,3-dienes is reinforced by conventional transition metal catalysts and by new organolanthanide catalysts. Nonconjugated dienes also polymerize selectively to produce polymers with cyclic units or vinyl pendant groups. Living polymerization of dienes has become common, which enabled preparation of block copolymers of dienes with alkenes and other monomers. Another new topic in this field is the polymerization of allenes and methylenecycloalkanes catalyzed by late transition metal complexes. These reactive dienes and derivatives provide polymers with novel structure as well as functionalized polymers. The precision polymerization of 1,2-, 1,3-, and l,n-dienes, achieved in recent years, will be developed to construct new polymer materials with olefin functionality. 

The data are consistent with polymer formation by way of phenyl radical reaction with benzene or the fulvene produced to give cyclic radical intermediates which then polymerize to yield a polycyclopentene chain with pendant phenyl and/or benzyl groups. The average non-olefinic to olefinic proton ratio of 2.9 indicates that the many possible... 

Mixtures of PPE and PS, or styrene-butadiene-styrene block copolymers have been extruded with maleic anhydride of fumaric acid to obtain compatibi-lized blends [42], In the same way, PPE with pendant glycidyl groups can be co-extruded with a poly(olefin) having anhydride groups [28], PPE can be grafted onto poly(ethylene) by melt kneading both modified polymers in the presence of a binder such as phenylenedi-amine. Both polymers are modified with maleic anhydride. The grafting takes place in situ. Amines may enhance the improvement of certain physical properties when used in combination with various compati-bilizers [29]. 

Fig. 21. Olefin functionalization of acrylic polymers through reaction with pendant hydroxyl groups.

The copolymerization of nonconjugated dienes with monoolefinic vinyl monomers is also known.Depending upon the comonomer pair and the copolymerization conditions, the product copolymer may contain (1) cyclized units made from sequential addition of both ends of the diene monomer (2) cyclized units made from addition of one end of the diene followed by the monoolefin comonomer or one side of a second diene, followed by the other end of the first diene (3) non-cyclized diene units bearing pendant olefins, and (4) crosslinked dienes formed by incorporation of these pendant olefins into another polymer chain (Scheme 19.1). For symmetrical, nonconjugated dienes, it has been shown that all of the well-known methods of polymerization can be employed to... 

The anionic polymerization of alloocimene with a catalyst system comprising a metal, e.g., sodium, and an aliphatic ether, e.g., 1,2-dimethoxyethane, yields a polymer with predominantly 2,3- and 6,7-tmits, and hence pendant dimethylbu-tadienyl groups (see Fig. 3). Polyalloocimenes with such a microstructure are especially useful as reactive intermediates, for instance readily forming Diels-Alder adducts with activated olefins [41]. 

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