JPH08208730A - Free-radical polymerizing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a free-radical polymn. process for producing a thermoplastic resin having a narrow polydispersity and useful as a toner resin material by adopting a free-radical polymn. process using an ultrasonic energy and enabling the selection of a low temp.

SOLUTION: The process comprises heating the first mixture comprising a free-radical initiator, a stable free-radical reagent, and at least one polymerizable monomer to form the first intermediate resin, cooling and isolating the first intermediate resin, adding the second mixture contg. at least one polymerizable monomer different from the monomer in the first mixture, heating to form the third mixture, cooling it, isolating the resulting resin, and if necessary washing and drying the resin. The heating is performed at about 40-100°C under ultrasonic irradiation. The stable free-radical reagent is pref. 2,2,6,6- tetramethyl-1-piperidinyloxy (TEMPO) and is used in a molar ratio to the initiator of about 2.5-0.5. The process can be repeated continuously.

COPYRIGHT: (C)1996,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for preparing a polymer including a homopolymer, a random copolymer, a block copolymer, a functionally activated polymer and the like, more specifically, a polymerization method and a method for forming the same. The polymer is In particular,
It relates to a method for preparing multi-blocks such as copolymers of styrene acrylate.

[0002]

BACKGROUND OF THE INVENTION The present invention is directed to narrow polydispersi.
ties), that is, where Mw is the weight average molecular weight and Mn is the number average molecular weight, the narrow molecular weight distribution shown by the ratio Mw / Mn and the easily adjustable modalities.
a stable free-radical relaxed method for producing one or more thermoplastic polymer resins having at least one Under conditions of ultrasonic radiation, heating a mixture of a free radical initiator, a stable free radical reagent and at least one polymerizable monomer compound, and cooling the mixture to effect polymerization. To stop
It relates to a method comprising isolating a thermoplastic resin product, optionally washing and drying the polymer resin product.
In the method of the present invention in one aspect, the temperature can be low, for example about 40 to about 100 ° C. The polymeric resin produced by the method of the present invention in one aspect comprises:
In one embodiment, which is essentially a monomodal and repeats the heating and sonication steps, ie, the combined initiation and polymerization steps, a single modality of polymer resin (ie narrow polydispersity and known or selectable) There is provided a means of obtaining a mixture of compositionally identical resin types) having both properties of different modalities. In some embodiments, the methods of the present invention provide a means for conducting bulk or net free radical polymerization processes on the order of kilograms or larger. Certain embodiments described above can be carried out in a single or single pot reactor environment. Further, in some embodiments, polymer chain growth proceeds by a pseudoliving mechanism,
Provide thermoplastics of various molecular weights, from very low to very high, eg from less than about 2,000 to about 300,000, while maintaining a narrow molecular weight distribution or polydispersity, eg from about 1.05 to about 1.95. The conversion of monomer to polymer is high, for example at least about 50%, and more particularly from about 50 to about 99-100%. Further, in some embodiments,
Block copolymers can be synthesized by the stable free radical-relaxed free radical polymerization method described above, and each block formed is sufficiently specified in length by the reacted monomer, for example. , Each of the formed blocks has a narrow molecular weight distribution, the block copolymer is substantially 100% block copolymer, and the formation of the homopolymer of the second monomer is not mixed. . The formation of the homopolymer of the second block monomer is carried out by the Otsu's iniferter (ini
ferter) is a possible competing reaction that occurs in other prior art, such as that of ferter).

One method for preparing narrow, molecular weight disperse or polydisperse polymers or copolymers is the anionic process. The applications and uses of resins having narrow polydispersity in industrial applications are inherently limited. This is because the anionic polymerization process is carried out in the absence of atmospheric oxygen and humidity and requires a difficult to handle and dangerous initiator. Thus, such polymerization processes are generally limited to small batch reactors. Furthermore, the monomers and solvents utilized must be highly pure and anhydrous. It makes the anion process much more expensive than alternative methods that do not require such requirements. Therefore, it is desirable to provide a free radical polymerization process that provides a narrow molecular weight distribution resin without the drawbacks of the anionic processes described above.

US Pat. No. 4,581,429 to Solomon et al. Is a free-radical polymerization process for controlling the growth of polymer chains which comprises predominantly short chain or oligomeric homopolymers and copolymers, including block and graft copolymers. Are disclosed.

US Pat. No. 5,322,912 exemplifies a free radical method for preparing thermoplastics.

[0006]

There is a need for a process for the preparation of narrow polydisperse polymeric resins by free-radical polymerization techniques which are economical and scalable. While avoiding problems such as gel formation, heat generation, multi-step reaction system with limited capacity, purification, performance characteristics of polymer chain products, etc., which accompany the methodology of free radical polymerization by, for example, hardness, low gel content, It retains many or all of its desirable physical properties such as processability, transparency and high gloss durability. Also, with the method of the present invention, lower temperatures can be selected and the rate of polymerization can be increased, so that, for example, the reaction time required to achieve a conversion of greater than about 90% is By using sonication, it is less than 6-7 hours, preferably about 3-5 hours.

The thermoplastic resin product of the present invention can be selected for a number of applications, such as toners, developers, and more particularly as a toner resin for electrostatographic imaging processes, and is also a single resin. Mixtures of single modality narrow molecular weight resins or block copolymers having a narrow molecular weight distribution within the modality or respective block component are suitable, for example, in thermoplastic film and coating technology.

It is an object of the present invention to use ultrasonic energy to select narrow temperatures, for example from about 40 to about 100, more particularly from about 50 to about 70 ° C., a narrow polydisperse homopolymer or It is to provide a free radical polymerization reaction system which gives a copolymer thermoplastic resin product.

Another object of the present invention is the use of ultrasonic energy to increase the rate of polymerization so as to reduce the time required to polymerize the monomers into the polymer, a narrow polydisperse single polymer. It is an object of the present invention to provide a free radical polymerization reaction system which gives a combined or copolymer thermoplastic resin product.

Yet another object of the present invention is a living stable free radical polymerization process which utilizes ultrasonic energy for initiation, wherein, for example, ultrasonic waves are applied to the polymerization of the monomers, thus increasing the polymerization temperature. It is an object of the present invention to provide a method capable of reducing a homopolymer and a block copolymer.

Another object of this invention is in the range of about 100: 1 to about 1: 1 and preferably about 20 to increase the rate of reaction by at least a factor of 3 without broadening the polydispersity of the polymer resin. It is possible to choose the addition of small amounts of organic acids with a stable free radical to organic acid molecular ratio in the range of: 1 to about 5: 1, where the acid is, for example, sulfonic acid, phosphoric acid, or benzoic acid. Such as carboxylic acid, camphor sulphonic acid, and further contains nitroxide stable radicals, which have acidic functional groups such as 2,2,
It shall contain 5,5-tetramethyl-3-carboxyl-1-pyrrolidinyloxy.

The object of the present invention is from about 1.05 to about 1.9.
5, preferably a resin having a Mw / Mn ratio of about 1.1 to about 1.6, at a low temperature, preferably about 40 to about 100.
A method of preparing at ℃, for example, at least 50%,
Another object of the present invention is to provide a method for preparing a resin which enables a high monomer-to-polymer conversion rate of about 50 to about 100, or 50 to 95%.

Still another object of the present invention is to provide a homopolymer,
Provide a stable free radical polymerization method for obtaining, for example, styrene homopolymers, random copolymers, block copolymers, multi-block copolymers, etc., especially styrene acrylate, styrene methacrylate, styrene butadiene. Generally, A, A
A, AB, BA, AAA, ABA, BAB, AABBA
It is intended that B, ABC, homopolymers and copolymers can be obtained by the method of the present invention in its various aspects.

[0014]

These and other objects of the present invention can be achieved by the present invention by a free radical polymerization process carried out at low temperatures using ultrasonic radiation.

The present invention relates to a free radical polymerization process for the preparation of thermoplastics, the first mixture comprising a free radical initiator, a stable free radical reagent and at least one polymerizable monomer compound. Is heated to form a first intermediate product resin, the first mixture is cooled, the first intermediate product resin is isolated, and at least one of the first intermediate product resins is added to the first intermediate product resin. A second mixture containing a polymerizable monomer compound is added, wherein the polymerizable monomer compound of the second mixture is different from the polymerizable monomer compound of the first mixture, and thus A thermoplastic comprising a first product resin formed from a first intermediate product resin and the second monomer added to form a combined mixture and heat the combined mixture. Made of resin Mixture of 3 was formed, cooling said third mixture, said third mixture of the thermoplastic resin was isolated from the, if necessary, washing the said thermoplastic resin,
Further drying, where said heating is a free radical polymerization process carried out in the presence of ultrasonic radiation at a temperature of about 40 to about 100 ° C.

The process of the present invention comprises a free radical polymerization process which comprises a free radical initiator, a stable free radical reagent, and at least one polymerizable monomeric compound in the presence of low temperature and ultrasonic energy. And heating the mixture to form one or more thermoplastics having a high conversion of monomer to polymer, cooling the mixture, and optionally isolating the one or more thermoplastics. , And optionally washing and drying one or more thermoplastic resins, wherein the one or more thermoplastic resins are, for example, from about 1.05 to about 1.95, preferably about 1.
It has a narrow polydispersity of 1 to about 1.6.

[0017]

One aspect of the present invention is directed to a free radical polymerization process for the preparation of thermoplastics, which comprises a free radical initiator, a stable free radical reagent, and at least one A first mixture containing a polymerizable monomer compound is heated to form a first intermediate product resin, and the first mixture is cooled if necessary, and the first intermediate product resin is A second mixture comprising a free radical initiator, a stable free radical reagent, and at least one polymerizable monomer compound is added, wherein the one or more polymerizable monomers of the second mixture. Is the same as the one or more polymerizable monomers of the first mixture, and the free radical initiator and the stable free radical reagent of the second mixture are the same as the free radical initiator and the stable radical of the first mixture. Free radio The same or different than the reagent and thus forming a combined mixture, heating the combined compound at low temperature in the presence of ultrasonic energy and adding a first intermediate resin with a second one or more A third product resin formed of a first product resin formed of a second monomer and a second product resin formed of a second one or more monomers; Forming a mixture, cooling the third mixture, optionally isolating the mixture of thermoplastic product resin from the third mixture, optionally washing and drying the mixture of thermoplastic resins. Including the first product resin and the second product resin,
Each having a narrow polydispersity, the mixture of thermoplastics has a modality equal to about 1 to about 2. If desired, an effective amount of fresh or fresh mixture of one or more monomers, a free radical initiator and a stable free radical reagent is subsequently added prior to the final cooling and isolation steps. Thereby, a high modality, for example about 3 to about 20, can be conveniently achieved.

Further, in one aspect of the invention there is provided a free radical polymerization process for the preparation of one or more block copolymer thermoplastics, which comprises from about 40 to about 10.
A first mixture comprising a free radical initiator, a stable free radical reagent, and at least one polymerizable monomer compound is heated in the presence of ultrasonic energy at a low temperature of 0 ° C. to heat the first mixture. Forming an intermediate product resin, cooling the first mixture, isolating the first intermediate product resin, and adding at least one polymerizable monomeric compound (block copolymer) to the first intermediate product resin. When preparing a coalescence, usually one monomer is added at a time and then polymerization is carried out, and then the next monomer is added, so there are many steps or the number of times that different monomers can be added. , But each time only one monomer is added) is added), wherein the polymerizable monomer compound of the second mixture is added to the mixture of the first mixture. Unlike polymerizable monomers, form a mixture thus combined And the combined mixture at low temperature by heating in the presence of ultrasonic energy, the first formed from the second monomer was added to the first intermediate product resin
Forming a third mixture containing the block copolymer thermoplastic resin containing the product resin of, cooling the third mixture, and optionally isolating the block copolymer thermoplastic resin from the third mixture. Optionally washing and drying the block copolymer thermoplastic, said block copolymer having a narrow polydispersity and a modality equal to 1. Isolation of the intermediate product resin is preferred when high purity and block integrity or homogeneity is desired.
That is, the remaining unreacted monomer (s) of the first mixture subsequently reacts with the growing polymer chains formed from the second mixture of polymerizable monomeric compounds, thereby May be incorporated. Thus, in preparing block copolymers by the method of the present invention, if high purity is desired, or if the degree of polymerization is less than about 70-90% for block or multiblock polymerization reactions,
Isolation is preferred, for example, by precipitation of an intermediate product of the polymerization reaction.

The polymerization method provides homo acrylate and copolymer acrylate resins having narrow polydispersity properties, the polymerization method proceeds at a high conversion rate of monomer to polymer, A copolymer containing acrylate and homoacrylate moieties is produced, the number average molecular weight (Mn) of which exceeds about 100 up to about 1,000, of the weight average molecular weight (Mw) relative to the number average molecular weight (Mn). The polydispersity ratio is from about 1.0 to about 2.0, preferably from about 1.1 to about 1.6, and in some embodiments stable free radical reagents include 4-
Oxo-2,2,6,6-tetramethyl-1-piperidinyloxy (4
-Oxo-TEMPO) can be selected.

According to the present invention, in one aspect there is provided a pseudo-living polymerization process that allows the synthesis of narrow polydisperse homoacrylate and copolymer acrylate resins from acrylate and acrylate derivative monomers. It This method uses, in one embodiment, known free radical initiators in combination with oxygenated stable free radical reagents and acrylate monomers to provide narrow polydisperse homoacrylate and copolymer acrylate resins. can do.

In one embodiment of the method described above, a polymer or copolymer resin composition is obtained, wherein the one or more product resins have a weight average molecular weight (M) of from about 2,000 to about 300,000.
w) and a number average molecular weight of about 1,800 to about 153,000 (M
n) and a polydispersity of about 1.05 to about 1.95,
More specifically, Mw / Mn is from about 1.1 to about 1.6, about 1.1 to about 1.5, or slightly greater than about 1 to about 1.6.

The process of the present invention, in some embodiments, further comprises means for continuously repeating the monomer addition or polymerization steps, wherein the additional stable free radical and free radical initiator of the process is added to the N2. Once added, it should give a well-specified mixture of thermoplastics, each resin in the mixture being composed of a polymer with a distinct and narrow polydispersity, N being an initiator, a stable free radical. The mixture has a modality equal to N + 1, given the number of times the reagent and monomer addition steps are repeated.

Using the method of the present invention, the polydispersity of the polymer product is narrowed and the ratio of the stable free radical reagent to the free radical initiator molecular concentration is varied to produce a monomer / comonomer About 1.05 depending on the system
It can vary between about 1.95. If the polymerization process conditions of the present invention are attempted without the use of SFR additives, a broad molecular weight resin with a polydispersity of 2-6 is obtained.

The stable free radical reagent moderated polymerization reaction is carried out in a variety of media, such as suspension, emulsification, bulk or net or without solvent, or in aqueous or non-aqueous solutions. However, high boiling solvents such as toluene and xylene should preferably be used.

In the reaction of the monomers to form the polymer or the mixed monomers, the reaction time is, for example, about 1 to about 6
Fluctuating between 0 hours, but preferably about 2-10 hours,
The optimum time is about 4 to 7 hours. The optimum reaction time is temperature,
It may vary depending on the volume and scale of the reaction and the amount and type of polymerization initiator and stable free radical reagent selected. The polymerization reaction temperature is kept relatively constant throughout the heating process by providing an adjustable external heat source, the temperature is about 40 ° C to about 100 ° C, preferably about 5 ° C.
Maintain at 0 ° C to about 75 ° C.

The free radical initiator selected may be any free radical polymerization initiator capable of initiating the free radical polymerization process, peroxide initiators such as benzoyl peroxide, and azo initiators such as Benzoyl peroxide is preferred, including azobisisobutyronitrile and the like. The concentration of the initiator used is 0.2-6% by weight of the total weight of the monomers to be polymerized and is determined by the desired molecular weight of the resin. The molecular weight of the thermoplastic resin product increases as the concentration of the initiator decreases with respect to the molar equivalent weight of the monomers used. The free radical initiator is added as a separate component to the reaction mixture and should not react with the stable free radical reagent prior to its use in the methods presented herein.

Examples of stable free radical reagents or components that can be selected include nitroxide free radicals such as proxil (2,2,5,5-tetramethyl-1-pyrrolidinyloxy), 3-carboxy-proxyl, 3- Carbamoyl-proxyl, 2,2-dimethyl-4,5-cyclohexyl-proxyl, 3-oxo-proxyl, 3-hydroxylimine-proxyl, 3-aminomethyl-proxyl, 3-methoxy-proxyl, 3-t-butyl- Proxy, 3-maleimido-proxyl, 3,4-di-t-butyl-proxyl, 3-
Carboxylic-2,2,5,5-tetramethyl-1-pyrrolidinyloxy and its derivatives, and TEMPO (2,2,6,6
-Tetramethyl-1-piperidinyloxy), 4-benzoxyloxy-TEMPO, 4-methoxy-TEMPO, 4-carboxylic
-4-amino-TEMPO, 4-chloro-TEMPO, 4-hydroxylimine-TEMPO, 4-hydroxy-TEMPO, 4-oxo-TEMPO, 4-
Oxo-TEMPO-ethylene ketal, 4-amino-TEMPO, 2,
2,6,6-Tetraethyl-1-piperidinyloxy, 2,2,6-trimethyl-6-ethyl-1-piperidinyloxy and the like, and derivatives thereof, and dialkyl nitroxide radicals such as di-t-butyl nitroxide, diphenyl nitroxide, t -Butyl-t-amyl nitroxide and its derivatives, and DOXYL (4,4-dimethyl-1-oxazolidinyloxy), 2-di-t-butyl-doxyl, 5-decane-doxyl, 2-cyclohexane- Doxyl and the like, and derivatives thereof, and 2,5-dimethyl-3,4-dicarboxylic-pyrrole, 2,5-dimethyl-3,4-diethyl ester-pyrrole, 2,3,4,5-tetraphenyl- Pyrrole, etc., and 3-cyano-pyrroline-3-carbamoyl-pyrroline, 3-carboxylic-pyrroline, etc., 1,1,3,3-tetramethylisoindoline-2-yloxyl and 1,1,3,3-tetraethyl Isoin Phosphorus-2 Irokishiru like, porphylene lexical nitroxyl radical, such as 5-cyclohexyl porphylene lexical nitroxyl and 2,2,4,5,5- pentamethyl -Δ
³ -imidazoline-3-oxide-1-oxyl, etc., and galbinoxyl, etc., 1,3,3-trimethyl-2-azabicyclo [2,2,2] octane-5-one-2-oxide and 1-azabicyclo [3 , 3,1] nonane-2-oxide and the like are included, and TEMPO is preferable. However, under the polymerization conditions of the present invention, stable free radical reagents act primarily as palliatives to utilize the normally reactive and indiscriminate intermediate free radical species. Nitroxide is Fr
Includes N, N-disubstituted nitroxides such as emy's salt (Fremy's salt).

The molecular ratio of the stable free radical (SFR) reagent to the free radical initiator (INIT) is about 2.5-.
The range is 0.5, preferably about 2.0 to 0.9. Without wishing to be bound by theory, in some embodiments, about 1.3 to 1 of a stable free radical reagent, such as TEMPO, to a free radical initiator, such as benzoyl peroxide. Molecular ratio [SFR:
INIT] is considered important. In some embodiments, if [SFR: INIT] is too high, the reaction rate may decrease. If [SFR: INIT] is too low, the reaction product will have an undesirably increased polydispersity. Also, polymerizing styrene to polystyrene without the use of the stable free radical reagent of the present method results in an isolated product polymer having a polydispersity of 2.0 or greater.

In one embodiment, the molecular ratio of monomer content to stable free radical reagent to free radical initiator is from about 10: 0.5: 1 to about 10,000: 5: 1, preferably about 300 :. The range is from 1.3: 1 to about 7,000: 1.3: 1. Of importance in some embodiments is a stable free radical to initiator molecular ratio of from about 1.3 to about 1 particularly for the polymerization of styrene. For monomers other than styrene, such as acrylates, a similar ratio is chosen, namely 1.3: 1.

The method of the present invention provides, in one embodiment, a high conversion of monomer to polymer, or a degree of polymerization, for example, in some embodiments 90% by weight or more, more specifically about 75%. ~ About 100%. Further, the method of the present invention, in some embodiments, provides a relatively high weight average molecular weight of the polymer product, wherein the weight average molecular weight is about 2,
000 to about 300,000 with a preferred range of about 2,000
~ About 250,000. In some embodiments, the method of the present invention can be used to obtain a polymer having a Mw of about 500,000.

Monomers of choice include those capable of undergoing free radical polymerization, including, but not limited to, styrene, substituted styrenes and their derivatives such as α-methylstyrene, 4- Methylstyrene, butadiene and any conjugated diene monomer that is sufficiently active and provides stable free radical reaction adducts and high molecular weight polymer products under moderated free radical relaxed polymerization reaction conditions, Examples include isoprene and myrcene, acrylates and their derivatives. Examples of the obtained polymer include styrene, acrylate, styrene acrylate, styrene butadiene and the like. The acrylate polymerization of the reaction of the present invention, in some embodiments, contributes to supplementing the solvent or co-solvent to ensure that the reaction mixture maintains a homogeneous single phase throughout the conversion of the monomers. It shall be. To select any solvent or co-solvent as long as the solvent medium is effective to allow the solvent system to avoid precipitation or phase separation of reactants or polymer products until after all polymerization reactions are complete. You can Exemplary solvents or co-solvents include polymer product compatible aliphatic alcohols, glycols, ethers,
Glycol ether, pyrrolidine, N-alkylpyrrolidinone, N-alkylpyrrolidinone, polyethylene glycol, polypropylene glycol, amides, carboxylic acids and their salts, esters, organic sulfides, sulfoxides, sulfones, alcohol derivatives, hydroxy ether derivatives, such as butyl CARBITOL (registered Trademark) or CELL
Included are OSOLVE®, amino alcohols, ketones, and their derivatives and mixtures thereof. Specific examples include ethylene glycol, propylene glycol, diethylene glycol, glycerin, dipropylene glycol, tetrahydrofuran, etc., and mixtures thereof. When a mixture of water and a water-soluble or miscible organic liquid is selected as the reaction medium, the weight ratio of water to cosolvent is typically about 100: 0 to about 10: 9, preferably about 97 :. The range is from 3 to about 25:75.

In one embodiment, the reaction time can be increased from about 16 hours or more to about 4 to 7 hours by adding a catalytic amount of a protic acid which can accelerate the rate of polymerization of the monomers and which cannot initiate cationic polymerization. Can be reduced to This acid is an organic acid such as sulfonic acid, phosphoric acid, carboxylic acid,
And selected from the group consisting of acid functionalised nitroxides, for example 3-carboxyl-proxyl, camphor sulphonic acid is the preferred acid. The molecular ratio of stable free radical to acid can vary, but can be, for example, about 100: 1 to 1: 1 with a suitable ratio of about 20: 1 to 5: 1. Excessive addition of organic acid in excess of the above amounts broadens the polydispersity of the resin in certain embodiments.

The stable free-radical relaxed polymerization process of the present invention can be repeated many times in the same reaction vessel by delaying the addition of one or more monomers and adding more in stages. The amounts of agent and stable free radical reagent are varied to form a single modality resin mixture, where each component has a distinct molecular weight and a narrow molecular weight distribution, and N is a mono The mixture has a modality of N + 1 as an indication of the number of additional additions of the body, initiator, and stable free radical reagent.

Cooling, which can be accomplished by turning off the heating source, such as an oil bath, removing the vessel from the oil bath and allowing it to cool naturally while maintaining agitation, causes the polymerization reaction to reach ambient temperature. Effectively calm or stop the relaxed reaction with stable free radicals. Monomers, stable free radicals, while heating with ultrasonic waves,
The addition of new and subsequent initiators and new initiators gives new polymer species with a narrow molecular weight distribution, each new polymer species being independent of the other previously formed polymer species. Continue to grow.

Alternatively, a block copolymer resin can also be prepared, whereby after each desired block is formed, a fresh one or more new initiators or stable free radical reagents are added without further addition. When multiple monomers are added to form a new block, each block component becomes
It will be well defined in length, have a narrow molecular weight distribution, and will have properties depending on the monomer selected for repeated procedures and blending.

Additional optional known additives may be selected in the polymerization reaction, which may provide additional performance enhancement to the resulting product, for example, Colorants, lubricants, mold release or transfer agents, surfactants, stabilizers, defoamers and the like.

Separate mix of single modalities (monomodals), ie, well-specified multimodalities (multim)
Polymeric resins having a molecular weight distribution of odal) have, in certain embodiments thereof, melt rheological properties, including improved flow and elasticity, especially for electrostatographic toner compositions.
And offers several advantages such as improved performance characteristics such as tribocharging, mixing speed, and storage stability.

The method of the present invention can be selected to form a wide variety of polymers. For example, it can be used to polymerize styrene monomers to form polystyrene, butadiene to form polybutadiene, or n-
Butyl acrylate can be polymerized to form poly (n-butyl acrylate). The method of the present invention can be selected to polymerize a mixture of two or more different polymerizable monomers to form a copolymer thereof, such as polymerization of styrene and butadiene to form poly (styrene-butadiene). , Polymerization of styrene and isoprene to form poly (styrene-isoprene), polymerization of styrene and ethyl acrylate to form poly (styrene-ethyl acrylate), and combinations thereof. A polymer is included.

Suitable reaction media used to carry out the process of the present invention include bulk or net suspension, emulsification, and solution systems.

In one embodiment, the monomer is about 1,000.
Waxy components having a low molecular weight of about 20,000, such as polyethylene, alkylenes such as polypropylene wax, and mixtures thereof can be admixed. The use of this type of component is desirable for certain toner applications. Suitable low molecular weight waxes such as polyethylene and polypropylene are disclosed in US Pat. No. 4,659,641.
This disclosure is incorporated herein by reference.

Toner compositions can be prepared by a number of known methods, such as resin particles obtained by the method of the present invention, such as styrene butadiene copolymer.
Pigment particles, such as magnetite, carbon black, or mixtures thereof, and cyan, yellow, magenta, green, brown, red, or mixtures thereof, and preferably about 0.5% to about 5% charge enhancing additive. And are mixed and heated in a toner extrusion device, such as ZSK53 available from Werner Pfleiderer, to remove the formed toner composition from the device. After cooling, for the purpose of achieving toner particles having a volume median diameter of less than about 25 microns, preferably about 6 to about 12 microns, for example,
The toner composition is subjected to milling using a Sturtevant micronizer. The diameter is measured with a Coulter Counter. The toner composition can then be classified, eg, using a Donaldson Model B classifier, for the purpose of removing toner particles, ie, toner particles less than about 4 microns in volume median diameter.

The toner composition of the present invention and external additive particles containing a flowability auxiliary additive can also be blended, and the additive is usually present on the surface thereof. Examples of these additives are fumed silica such as AEROSI.
L <(R)>, metal salts and metal salts of fatty acids including zinc stearate, aluminum oxide, cerium oxide, and mixtures thereof, these additives generally comprising from about 0.1% to about 5% by weight. %, Preferably about 0.1% to about 1% by weight.

It is also possible to include low molecular weight waxes in the toner composition, which may be, for example, Allied C
Eastman Chemic, polypropylene and polyethylene commercially available from hemical and Petrolite Corporation
EPOLENE N-15 available from al Products, Inc.
(Registered trademark), VISCOL 550-P (registered trademark), Sanyo Kase
Low weight average molecular weight polypropylene, commercially available from iKK, and similar materials.

Included within the scope of this invention are colored toner and developer compositions, which include toner resin particles, carrier particles, charge enhancing additives (shown here), and pigments or colors. Agents include red, blue, green, brown, magenta, cyan and / or yellow particles, and mixtures thereof.

To prepare the developing composition, the toner particle carrier components are mixed. The carrier particles are selected to be of a negative polarity that allows the positively charged toner particles to adsorb and surround the carrier particles. Examples of carrier particles include iron powder, steel, nickel, iron, ferrites including copper-zinc ferrite, and the like. In addition, U.S. Pat.
Nickel berr as shown in No. 604
y) The carrier can be selected as carrier particles. The selected carrier particles can be used with or without a coating, but the coating generally contains a terpolymer of styrene, methyl methacrylate, and a silane such as triethoxysilane, Reference may be made to US Pat. No. 3,526,533, US Pat. No. 4,937,166, and US Pat. No. 4,935,326. For example, a mixture (40/60) of KYNAR (registered trademark) and polymethylmethacrylate is included. The coat weight may vary as indicated herein, but generally a coat weight of about 0.3 to about 2, preferably about 0.5 to about 1.5% by weight should be selected.

Further, the diameter of the carrier particles, which are preferably spherical in shape, is generally from about 50 microns to about 1,000 microns, and in some embodiments from about 70 to about 175 microns.

Toner compositions prepared from the resins of the present invention are also known when using one aspect of the charge enhancing additives of the desired narrow charge distribution, about 0.1 to about 5% by weight. Preferably 10 to about 50, more preferably about 1 per gram as measured by the Faraday Box method.
Optimal charge triboelectric charging value from 0 to about 35 microcoulombs,
And having a rapid charge time of less than 15 seconds as measured by a charge spectrograph, and more preferably in some embodiments from about 1 to about 14 seconds.

[0048]

EXAMPLES In all of the method examples except Comparative Example 1, the ultrasonic radiation source as described in Example 1 was used, and the low temperature was 40 to 70 ° C. Comparative examples and data are also shown. Parts and percentages are by weight unless otherwise indicated. A comparative example is also shown.

Comparative Example 1 Styrene suspension suspension without using a stable free radical reagent
Alkanol (Alkano) in free radical polymerized water (100 ml)
l, 48 mg) tricalcium phosphate (3.
0 grams) and naphthalene sulfonate available from DuPont are added to the modified Parr reactor and the reactor is purged with nitrogen for 8 minutes over 8 minutes.
Heated to 0 ° C. Under 60 pounds of nitrogen per square inch, a solution of benzoyl peroxide (2.0 grams, 0.008 moles) in styrene (78 grams, 0.75 moles) was added to the reactor and heated at 80 ° C for 3 hours 20 hours. The reaction was continued for a minute.
Then, it heated at 95 degreeC and continued the reaction at that temperature for 2 hours and 20 minutes. Samples were removed from the reactor at the time intervals or reaction times (minutes) shown in Table 1 (0.5-1.0 grams in the examples unless otherwise indicated), cooled, treated with concentrated nitric acid and suspended reagent. Was dissolved, rinsed with water and dried. The molecular weight characteristics of the intermediate material and the final polystyrene product are shown in Table 1. Polydispersity (Mw / Mn) is shown in the column labeled PD.

[0050]

[Table 1]

Example 1 Ultrasonic radiation using a stable free radical reagent (TEMPO)
50 equipped with an oil bath under the beaker to heat the bulk polymerization solution of styrene through
Styrene monomer (15 grams, 0.144 moles), benzoyl peroxide (0.052 grams, 0.215 millimoles), and a stable nitroxide radical, TEMPO (0.045 grams, per 0 milliliter metal beaker). 0.288 mmol) is added. After heating to a solution temperature of 60 ° C, 300 watt model ultrasonic horn (Cole-Parmer ultrasonic homogenizer 4710 horn)
Is placed in the monomer solution and the power adjustment setting is put in setting number 9 for 30 minutes. When ultrasonic energy is applied to the monomer solution, the metal beaker is moved in all directions in an oil bath to provide proper mixing of the solution during polymerization. At this stage, ultrasonic energy is continued for another 30 minutes after the sample of the solution is removed. This polymerization procedure is continued for a total of 4 hours. Samples (0.5 to 1.0 grams in each example unless otherwise indicated) are removed from the reaction mixture every 30 minutes and the molecular weight characteristics of the polystyrene product are measured. Mn for polystyrene is 8,826 and Mw is
38,965, and PD, polydispersity is 1.26. Mn
And Mw are refractive index detectors, HP1047, calibrated with polystyrene standards ranging from 2,000,000 to 500 Daltons.
Evaluate using a Hewlett Packard gel permeation chromatograph model HP1090 with A.

Example 1 shows that the reaction can be conveniently carried out in the absence of solvent or in bulk. The molecular ratio of TEMPO to benzoyl peroxide is 1.3: 1, which is the optimum ratio. This example also shows that overall reaction temperatures for moderated free radical polymerization of styrene can be achieved at low reaction temperatures and short times, while still producing polymers with excellent high molecular weight.

Example 2 Using a stable free radical reagent (4-oxo-TEMPO)
50 equipped with an oil bath under the beaker to heat the bulk polymerization solution of n-butyl acrylate via sonication
N-butyl acrylate monomer (15 grams, 0.117 mol), azobisisobutyronitrile (AIBN) (0.050 grams, per 0 milliliter metal beaker)
0.291 mmol), and a stable nitroxide radical, 4-oxo-TEMPO (0.085 grams, 0.500).
Mmol) is added. After heating to bring the temperature of the solution to 50 ° C., place a 300 watt model ultrasonic horn in the monomer solution and put the power adjustment setting in setting number 9 for 30 minutes. When ultrasonic energy is applied to the monomer solution, the metal beaker is moved in all directions in an oil bath to provide proper mixing of the solution during polymerization. At this stage, a sample of the solution (0.5-1 ..
After taking out 0 gram), add 3 more ultrasonic energy.
Continue for 0 minutes. This polymerization procedure is continued for a total of 4 hours. A 0.5-1.0 gram sample is removed from the reaction mixture every 30 minutes to determine the molecular weight profile of the poly (n-butyl acrylate) product. The Mn for poly (n-butyl acrylate) is 7,939, Mw is 12,247, and PD, polydispersity is 1.54. Mn and Mw are
Hewl with an HP1047A refractive index detector calibrated with polystyrene standards ranging from 2,000,000 to 500 Daltons
Evaluate using the ett Packard gel permeation chromatograph model HP1090.

Example 2 shows that the reaction can be conveniently carried out in the absence of solvent or in bulk. The molecular ratio of TEMPO to benzoyl peroxide was 1.7: 1, which is not considered to be the optimum ratio for this example, and the optimized ratio is narrower than the 1.54 obtained. Polydispersity will be possible. This example also shows that at low reaction temperatures and short times, the overall reaction temperature for moderated free radical polymerization of n-butyl acrylate can be achieved.

Example 3 Preparation and Evaluation of Magnetic Toner The polymer resin obtained by the stable free radical polymerization method of Example 2 (74% by weight of the total mixture) contained 10% by weight of REGAL 330® carbon. It can be extruded with black and 16 wt% MAPICO BLACK® magnetite at 120 ° C. and the extrudate milled in a Waring blender and jetted into 8 micron number average sized particles. Positively charged magnetic toner is 0.12 grams of AEROSIL R972 in a 1: 1 weight ratio.
(Registered trademark) (Degussa Chemicals) and TP-302, naphthalenesulfonic acid and quaternary ammonium salt (Nachem / Hod
ogaya SI) can be prepared by surface treating toner (2 grams) jetted with a charge control agent.

Then 3.34 parts by weight of the above toner composition was added to an upper polymer mixture (coating weight: 70% by weight KYNAR®, polyvinylidene fluoride and 30% by weight polymethylmethacrylate). Is about 0.9%), and by mixing with 96.66 parts by weight of a carrier comprising a steel core having a diameter of 98 microns,
A developer composition can be prepared. Cascade development can be used to develop Xerox Model D photoreceptors using "negative" targets. The exposure can be set to 5-10 seconds and a negative bias can be used to dark transfer the positive toner image from the photoreceptor to the paper.

The fusing evaluation can be carried out using a Xerox 5028® soft silicone roll fusing machine operating at 3 inches per second.

While a toner prepared from a resin synthesized by a free radical polymerization method without using a stable free radical reagent gives a wide polydispersity, a stable free radical polymerization having a narrow polydispersity as a toner. The minimum fixing and hot offset temperature (° F) of the polymer are expected to be improved. The actual fuser roll temperature can be measured using an Omega pyrometer and checked using a wax vapor indicator.
The extent of the developed toner image on the paper after fusing is evaluated using the Scotch tape test. Fixing levels are expected to be excellent and can be compared to fixings obtained with toner compositions prepared from other methods for preparing toners having resins with high molecular weight and narrow polydispersity. Typically 95% after stripping the tape as measured by a densitometer
Toner images that exceed 100 mm remain fixed on the copy sheet.

Aluminum support substrate, trigonal selenium photogenerating layer, arylamine N, N'-diphenyl-N,
N'-bis (3-methylphenyl) 1,1'-biphenyl-4,4'-
Images can be developed in a xerographic imaging tester equipped with a negatively charged layered imaging member composed of a diamine (45% by weight dispersed in 55% by weight polycarbonate MAKROLON®). (See US Pat. No. 4,265,990), images with toner compositions prepared from the polymer products of Examples 1 and 2 have been shown to have extended times beyond about 75,000 imaging cycles. Is expected to be of excellent quality and high resolution with no background deposits over the entire imaging cycle.

Other toner compositions can be readily prepared from the polymers and copolymers of the present invention by conventional means, including colored toners, single component toners, multicomponent toners, and specific performance toners. Toners containing additives and the like are included.

[0061]

Industrial Applicability The above-described stable free radical reagent-relaxed polymerization method can be applied to a wide range of organic monomers to provide a novel toner resin material having desired electrophotographic characteristics, coating and the like. . For example, the block copolymer is
It can be selected as the dispersion for the photoreceptor pigment. Multiple modality resins can be utilized as low melting toner resins, and some single modality resins can be used to modify the surface of carbon black and other pigment particles to make the pigment particles a host polymer or dispersion. It can be more miscible with the medium. Furthermore, it is narrow (PD)
Molecular weight resins such as poly (styrene-butadiene) are
It can be selected as an improved toner resin for copying applications.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Peter M. Katmaier Canada El 5 El 1 E 5 Mississauga Council, Ontario Ring Road 2421 (72) Inventor Michael Kay. Georges Canada N 1 G 3 N 8 Guelph Ironwood Road, Ontario 384 (72) Inventor Gordon Kay. Hummer Canada L5L2P4 Missouriau, South Ontario South Milway No. 1-2280 (72) Inventor Richard P.H. N. Verezin Canada El 5 El 5 Sea 3 Mississauga, State of Ontario Cherrington Crescent 3515 (72) Inventor Markody. Savan Canada M9B4N1Entobi Cork Charleston Road 65

Claims (3)

[Claims] 1. A free radical polymerization method for the preparation of a thermoplastic resin comprising heating a first mixture of a free radical initiator, a stable free radical reagent and at least one polymerizable monomer compound. Forming a first intermediate product resin, cooling the first mixture, isolating the first intermediate product resin, at least one polymerizable with respect to the first intermediate product resin, A second mixture containing a monomer compound is added, wherein the polymerizable monomer compound of the second mixture is different from the polymerizable monomer compound of the first mixture and thus combined. And a thermoplastic resin comprising a first product resin formed from the first intermediate product resin and the added second monomer is heated to form a thermoplastic resin. Including the third mixture Forming a substance, cooling the third mixture, isolating the thermoplastic resin from the third mixture, optionally washing the thermoplastic resin, and further drying, where the heating Is a free radical polymerization process carried out at a temperature of about 40 to about 100 ° C. in the presence of ultrasonic radiation. 2. A fourth mixture containing a multi-block copolymer thermoplastic resin having N + 2 [N is the number of repetitions] blocks, wherein the addition, heating and cooling are repeated N times continuously. Forming, and optionally isolating the multiblock copolymer thermoplastic from the fourth mixture, and optionally further washing and drying the multiblock copolymer thermoplastic, where The multi-block copolymer thermoplastic resin has a narrow polydispersity, and the heating does not occur. About 40-100
The method of free radical polymerization according to claim 1, which is carried out at a temperature of ° C, the heating being carried out in the presence of ultrasonic radiation. 3. The resin product has a narrow polydispersity,
Obtained with excellent conversion rate, which is about 50 to about 9
5%, its polydispersity is about 1.1 to about 1.8, and the ratio of stable free radical reagent to free radical initiator is about 0.5: 1 to about 20: 1. The free radical polymerization method according to claim 1.