This technology is available from Temarex Corporation.

STAR POLYMERS

 

Title: THREE ARM STAR COMPOSITIONS OF MATTER HAVING DIBLOCK

ARMS BASED ON POLYISOBUTYLENE AND METHODS OF

PREPARATION

 

Inventor(s): J. Kennedy, G. Fenyvesi, B. Keszler

 

Disclosure 362, U.S. Patent not yet issued

 

This invention relates to three arm star thermoplastic compositions of matter comprising an aromatic core having multiple arms radiating from the core, each arm having a rubbery inner segment of polyisobutylene connected to glassy outer polymeric segments, wherein the outer segments of each diblock arm are obtained by a novel polymerization process.

The thermoplastic composition of matter of the present invention has superior mechanical properties as compared to linear thermoplastic elastomers of the prior art. In one example, the present invention had a tensile strength of up to about 25 MPa, and an elongation of up to about 250 percent which is impressive when compared to the mechanical properties of a linear triblock TPE such as PMMA-b-PIB-b-PMMA. Star-blocks containing even relatively low molecular weight PMMA segments exhibited surprisingly high tensile properties.

The swelling kinetics of a three arm star-block thermoplastic elastomer of the present invention was evaluated. The results of the swelling studies indicate that the three arm star thermoplastic composition of matter of the present invention possess an amphiphilic nature which may have significant importance and value in some applications.

The compositions derived from the present invention can be used for any applications that traditionally utilize thermoplastic elastomers, including, but not limited to (hot melt) adhesive and coating compositions.

 

 

 

Title: DYNAMIC STAR POLYMERS AND A METHOD FOR THE SYNTHESIS

THEREOF

 

Inventor(s): J. Kennedy, M. Zsuga, S. Keki, G. Deak

 

Disclosure 320 U.S. Patent 6,130,291

 

This invention relates to multi-arm star polymers capable of changing their molecular structure under external influences.

In order to avoid decomposition upon exposure to high-heat or high-stress environments, the core of the star polymer must be ìdynamicî rather than ìstaticî wherein the core is capable of molecular shape change upon exposure to heat or other external influences. Not only do these starís core change upon exposure to external influences, but the core also returns to its original state upon the return of the previous conditions. This ìdynamicî viscosity is desirable in lubricant additives.

In order to effectively change molecular structure, it will be appreciated that the core of the star polymer must have segments which can separate upon changes in external conditions. Just as important, the process must be reversible, meaning the core segments should be able to relink upon a return of prior conditions.

Multi-arm star polymers are being investigated as rheology control agents, viscosity (index) modifiers, motor oil additives, coating and\or paint additives and the like. It will be appreciated that our star polymers may be useful in a variety of applications, including the manufacture of other materials.

 

Title: STAR-BLOCK POLYMERS HAVING MULTIPLE POLYISOBUTYLENE

CONTAINING DIBLOCK COPOLYMER ARMS RADIATING FROM A

SILOXANE CORE AND A METHOD FOR THE SYNTHESIS THEREOF

 

Inventor(s): J. Kennedy, J. S. Shim

 

Disclosure 318 U.S. Patent; Notice of Allowance (2001)

 

This invention relates to star-block polymers having well-defined arms emanating from a well-defined core and which enhances and extends previous star polymer technology.

The use of siloxane core as a starting material is likely to improve heat stability, and the use of isobutylene arms is likely to increase oxidation and ozonation resistance, as may be necessary in many applications. This composition is a candidate for high-value uses where basic commodity polymers fall short of required physical properties and use requirements.

It is believed that it is highly desirable to provide star-block TPEs which are believed to have superior mechanical, thermal and rheological properties (i.e. low viscosities) as compared to linear triblock TPEs or similar hard/soft segment compositions, including improved tensile strength and processing properties.

Based upon our market intelligence, it is believed that the improved processing properties should be of significant value to the molder (i.e. polymer suppliers' customers) as processing and/or molding costs is one of the biggest cost drivers, if not the biggest cost driver, to final product manufacturing cost.

Potential uses include viscosity control agents, a segment of the petroleum additive market, as thermoplastic elastomers (TPE), or as a compatibilizing agent in TPEs or polymer blends

 

Title: STAR POLYMERS HAVING MULTIPLE POLYISOBUTYLENE ARMS EMANATING

FROM A CALIXARENE CORE, INITIATORS THEREFOR, AND A METHOD FOR

THE SYNTHESIS THEREOF

 

Inventor(s): J. Kennedy, I. Majoros, S. Jacob

 

Disclosure 288 U.S. Patent 5,844,056

Disclosure 288-CIP U.S. Patent 5,804,664

 

This invention generally relates to star polymers and to carbocationic polymerization of monomers such as isobutylene via the "core first" method. Specifically, this invention relates to the synthesis of well-defined star polymers having well-defined arms of polyisobutylene (PIB) emanating from a calixarene derivative initiator which induce the living (carbocationic) polymerization of isobutylene or a similar carbocationically polymerizable monomer to form star polymers or block copolymers. The resultant star polymers have a well-defined core as well as well-defined arms.

These star polymers are advantageously "directly telechelic" meaning that the resultant star polymers will automatically have a functional group at the end of each arm of the star polymer upon termination of the polymerization reaction. That is, chain end functionality of the polyisobutylene arms is preserved during the formation of the star. In comparison, other star polymers require an additional process step to provide end chain functionality.

These multi-arm PIB star polymer compositions, unlike many other star polymers, have been found to be well-defined, both at the arms and core, and that have comparatively a more definite number of arms, a more definite arm molecular weight, a more definite core molecular weight and a narrower polydispersity (i.e. uniform arm length) than those stars having well-defined arms, but ill-defined cores.

Multi-arm star polymers are being investigated as viscosity modifiers, motor oil additives, paint additives and the like, although it will be appreciated that the subject star polymers may be readily useful in a variety of applications, including the manufacture of other materials as well. The synthesis of star block copolymers provide for the preparation of useful TPEs as well.

 

Title: MULTI-ARM STAR POLYMERS HAVING A WELL-DEFINED CORE AND

METHODS FOR THE SYNTHESIS THEREOF

 

Inventor(s): J. Kennedy, I. Majoros, T. Marsalko

Disclosure 278 U.S. Patent 5,840,814

 

This invention relates to star polymers having multiple, well-defined arms of polyisobutylene, polysiloxane and the like emanating from a well-defined calixarene core. The core is a ring-shaped or cyclic first component calixarene derivative.

A well known representative of this class of materials, currently commercialized by a major oil company, is a multi-arm star molecule consisting of many hydrogenated polyisoprene arms emanating from a core of crosslinked polydivinylbenzene (PDVB). While this star polymer is an excellent oil additive, the star polymers of the present invention are expected to be superior to it on the account of their structures. For example, the arms of current commercialized star polymers are made by hydrogenating (an expensive process) of polyisoprene; the hydrogenation is never complete (~4% of the double bonds of the polyisoprene remain unhydrogenated) and the surviving unsaturations impart oxidative and thermal vulnerability to the polymer. Also, the ill-defined gelly PDVB core contains unreacted double bonds whose presence is undesirable.

The multi-arm stars under the present invention comprise fully saturated polyisobutylene arms and well-defined calixarene ring cores which do not contain double bonds. As a result, the structure of the well-defined core as well as the structure of the resultant star polymers can be controlled.

This invention concerns at least three kinds of multi-arm stars: (1) polyisobutylene (PIB) arms connected to a calixarene derivative, (2) polysiloxane (PDMS) arms connected to a calixarene derivative and (3) PIB and PDMS mixed arms connected to a calixarene derivative.

The star polymers are ideally suitable as surfactants, lubricants, rheology modifiers, viscosity improvers, oil additives, in paints and the like.

 

Title: HIGHER ORDER STAR POLYMERS HAVING MULTIPLE POLYISOBUTYLENE

ARMS RADIATING FROM A CONDENSED CORE OF SILOXANES AND A

METHOD FOR THE SYNTHESIS THEREOF

 

Inventor(s): J. Kennedy, N. Omura, A. Lubnin

 

Disclosure 258-CIP U.S. Patent 5,856,392

 

This invention relates to "higher order" star polymers having multiple, well-defined arms of polyisobutylene (PIB) emanating from a condensed core of siloxanes. Higher order stars might be envisioned as clusters of first-order star polymers linked together by their siloxane cores.

A major advantage of these cyclosiloxane cores over those cores of PDVB is that these cores are individual, well-defined cyclic compounds and, therefore, yield relatively simple core architectures, as compared to the complex networks created by PDVB cores, whose characterization is practically impossible.

Higher order multi-arm star comprises many more PIB arms emanating from a complex core of condensed cyclosiloxanes than could be found on any one individual siloxane of a first order star. Additionally, the size of the core as well as the number of arms, which ultimately control rheological properties, can now be controlled.

Studies have demonstrated that silicon oils apparently have superior shear stability properties as compared to hydrocarbon oils. Thus it is seen as highly desirable to provide a star polymer having multiple well-defined PIB arms and a well defined, silicon-based core which would be shear stable.

In addition to shear stable, these higher order star polymers are acid-base stable as the PIB corona completely envelops and thus protects the vulnerable core. Additionally, the overall heat resistance of the stars were found to be similar to that of PIB.

Multi-arm star polymers are being investigated as rheology control agents, viscosity modifiers, motor oil additives and the like, although it will be appreciated that the subject star polymers may be readily useful in a variety of applications, including the manufacture of other materials as well.

 

Title: STAR POLYMERS HAVING A WELL-DEFINED SILOXANE CORE AND MULTIPLE

POLYISOBUTYLENE ARMS AND A METHOD FOR THE SYNTHESIS THEREOF

 

Inventor(s): J. Kennedy, N. Omura, A. Lubnin

 

Disclosure 258 U.S. Patent 5,663,245

 

This invention generally relates to star polymers having multiple, well-defined polyisobutylene arms emanating from well-defined siloxane cores.

Specifically, the invention relates to the synthesis of star-shaped polyisobutylenes by linking olefin-terminated polyisobutylenes with multi-functional cyclosiloxanes via hydrosilation.

A significant advantage of this invention is that star polymers having well-defined cores may exhibit better shear stability than star polymers with ill-defined cores. That is, the presence of unsaturated sites (i.e. double bonds) in ill-defined cores (i.e. crosslinked polydivinylbenzene [PDVB]) provides for the possibility that the resultant star polymers (i.e. prior art) will be less shear stable and more sensitive to oxidative reactions than star polymers having well-defined cores.

In engine oils where shear stability is of critical importance, the possibility exists that during high temperature use and heavy shear in the engine, the ill-defined cores will degrade, and this invention provides an improved alternative composition of matter.

A fundamental problem solved by this invention is that it is highly desirable to provide a star polymer having multiple well-defined polyisobutylene arms and a well-defined, silicon based core which would be shear stable. In addition, this star polymer composition would have a low viscosity and high molecular weight. These properties are highly desirable for a variety of applications.

These star polymers are ideally suitable for applications which include inter alia, surfactants, lubricants, rheology modifiers, viscosity modifiers, and oil additives.

 

Title: MULTI-ARM CATIONIC STAR POLYMERS

Inventor(s): J. Kennedy, I. Majoros, T. Marsalko

Disclosure 230 U.S. Patent 5,395,885

 

The first synthesis of a multi-arm radial-star polyisobutylene is described using a linking agent other than an ether-based compound. The star polyisobutylene synthesis proceeds by the addition of divinylbenzene (DVB) linking reagent to a living cationic polyisobutylene (PIB/), charge, i.e. by the "arm first" method under specific conditions. A representative star-PIB product would have a molecular weight distribution of w = 1,134,400 g/mole with w/n = 2.83, contained ~90.3 mole% (~78 wt. %) PIB arms and ~9.7 mole% (~22 wt.%) aromatic core. The number of PIB arms emanating from the core was n,arm = 56 or w,arm (weight average number of arms) = 110.

One of the key features of the invention is that it provides a synthetic route to polyolefin based, cationically synthesized, star polymers which have essentially no residual unsaturation subsequent to star formation, thereby eliminating the need for a post-hydrogenation step, when oxidative stability is necessary.

These polymers can be classified as friction, lubrication and wear technology materials. The star polymers are ideally suitable for applications which include motor oil viscosity modifiers and oil additives; fuel additives where low sulfur fuels are needed; and in paint and adhesives applications.