The present invention relates to a process for preparing a compound comprising macromolecular chains, using a diallylamine. The present invention also relates to a compound comprising macromolecular chains of controlled architecture, comprising units derived from a diallylamine.
Numerous controlled radical polymerization techniques have been developed in the last 10 years, enabling access relatively easily and inexpensively, from monomers, to a wide variety of macromolecular compounds. Examples that may be mentioned include ATRP techniques, and techniques using nitroxides or alkoxyamines that can generate nitroxides. These polymerization techniques have made it possible to design many novel macromolecular compounds, especially macromolecular compounds of controlled architecture such as block polymers, and to modulate many properties of such compounds. Numerous publications have reviewed controlled radical polymerization techniques, their applications on certain monomers, macromolecular compounds that can be obtained via these techniques, and their properties or uses.
However, for certain monomers, no suitable polymerization technique of controlled radical type has ever been described, and no macromolecular compound of controlled architecture derived from these monomers has ever been described. Limitations exist for the design and modulation of properties of macromolecular compounds, and for the manufacture thereof. There is a need for polymerization techniques and for polymers that are outside these limits. There is in particular a need for macromolecular compounds of controlled architecture bearing cationic or potentially cationic groups, which have great stability in many environments, modulated properties, a low cost price and/or are easy to access especially via the monomers used.
The invention satisfies at least some of the needs mentioned above, by proposing a process for preparing a compound comprising macromolecular chains, comprising a “step P” of radical polymerization in which the following are placed in contact:
The invention also proposes, in order to satisfy at least some of the needs mentioned above, a compound comprising macromolecular chains of controlled architecture, characterized in that:
It is mentioned that the compound of the invention can be obtained by means of the process of the invention. It is also mentioned that a controlled architecture of macromolecular chains comprising units derived from ethylenically unsaturated monomers is generally associated with a controlled or “living” polymerization process, preferably a controlled radical polymerization process. Controlled radical polymerization processes using transfer groups of formula —S—CS— allow access to such compounds. Such compounds may be prepared simply and/or economically via such processes.
In the present patent application, the term unit derived from a monomer, other than a monomer M denotes a unit that may be obtained directly from said polymerization monomer. Thus, for example, a unit derived from an acrylic or methacrylic acid ester does not cover a unit of formula —CH2—CH(COOH)—, or —CH2—C(CH3)(COOH)—, obtained, for example, by polymerizing an acrylic or methacrylic acid ester, followed by hydrolyzing. For example also, a unit derived from acrylic or methacrylic acid denotes a unit of formula —CH2—CH(COOH)— or —CH2—C(CH3)(COOH)— even if these units have been obtained by polymerizing an acrylic or methacrylic acid ester, followed by hydrolyzing.
In the present patent application, the term “unit derived from a monomer M” denotes a unit that may be obtained directly from said monomer, with a possible rearrangement such as a cyclization in the form of a heterocycle comprising a nitrogen atom, and, where appropriate, with a possible chemical modification (for example by chloroalkylation to quaternize a secondary amine).
In the present patent application, the term “monomer other than the monomer M” denotes a monomer that is not a ternary or quaternary diallylamine, where appropriate in the form of a salt, especially as described below. These monomers and the units derived therefrom are also noted as other monomers or other units.
In the present patent application, a “monomer composition” used during a polymerization step is defined by the nature and the relative amount of monomers. It may be a single monomer. It may be a combination of several monomers (comonomers), of different nature, in different proportions. Similarly, a composition of a macromolecular chain or a composition of units of a macromolecular chain is defined by the nature and the relative amount of the monomers from which the units of the macromolecular chain are derived. It may be a macromolecular chain derived from a single monomer (homopolymer chain). It may be a macromolecular chain whose units are derived from several monomers of different nature, in different proportions (copolymer chain).
In the present patent application, a “different monomer composition” denotes a composition in which the nature of the monomer(s) and/or in which the proportions of different monomers are different. This is likewise, by analogy, the case for a different macromolecular chain or a different unit composition. A monomer composition comprising 100% of a monomer M1 is different than a composition comprising 100% of a monomer M2. A monomer composition comprising 50% of a monomer M1 and 50% of a monomer A1 is different than a composition comprising 10% of a monomer M1 and 90% of a monomer A1. A monomer composition comprising 50% of a monomer M1 and 50% of a monomer A1 is different than a composition comprising 50% of the monomer M1 and 50% of a monomer A2.
In the present patent application, to simplify, the units derived from a monomer will occasionally be likened to the monomer itself, and reciprocally.
In the present patent application, an ethylenically unsaturated monomer is a compound comprising a polymerizable carbon-carbon double bond. It may be a monoethylenically unsaturated monomer, preferably an α-monoethylenically unsaturated monomer, or a polyethylenically unsaturated monomer. In the present patent application, for the different compounds of star copolymers or star microgels, and for different processes for preparing star copolymers or star microgels, an ethylenically unsaturated monomer denotes a monoethylenically unsaturated monomer, preferably an α-monoethylenically unsaturated monomer.
Monomer M and Units Derived from the Monomer M
The monomer M is a tertiary or quaternary diallylamine optionally in the form of a salt. It may be a mixture or a combination of several of these amines. It is mentioned that the monomer and the units derived from the monomer M may be in various forms, especially as a function of the pH of the medium in which they are present (protonation on acidifying). They may be in the form of salts, either permanently at any pH (quaternary amines), or as a function of the pH. Certain monomers M of quaternary amine type, and the units derived therefrom, bearing a substituent (of type R3 in particular) comprising a negative charge are occasionally referred to as betaines, and are not generally considered as being in the form of salts. The monomers M in the form of salts, and the units derived therefrom, generally comprise a counter-anion X−. Monomers M are, for example, monomers having the following formulae:
CH2═CH—CH2—NR1—CH2—CH═CH2 (I)
CH2═CH—CH2—N+R1R2—CH2—CH═CH2, X− (II)
CH2═CH—CH2—N+R1R3CH2—CH═CH2 (III)
in which:
Examples of monomers M that are mentioned include:
CH2═CH—CH2—N+(CH3)(CH2—CH2—CH2—SO3−)—CH2—CH═CH2
CH2═CH—CH2—N+(CH3)(CH2—CH2—CH2—COO−)—CH2—CH═CH2
Units derived from the monomers M may especially be in cyclized form, in the form of a heterocycle comprising a nitrogen atom. This cyclization may be due to a rearrangement that takes place during the polymerization step P. Advantageously, at least 50% by number, preferably at least 90%, or even all, of the units derived from the monomer M are in the form of a heterocycle comprising the nitrogen atom. This form may especially contribute toward good chemical stability of the compounds comprising the macromolecular chain, especially in hostile media in terms, for example, of pH, temperature and/or presence of molecules liable to degrade polymerized units, in particular cationic units.
The cyclization and the heterocycles may especially be revealed by NMR analysis (disappearance of the two allylic protons, characteristic shifts of the protons borne by the carbons adjacent to the heteroatom, and possibly characteristic shifts of these carbons).
The units derived from monomers M in the form of a heterocycle comprising a nitrogen atom may especially have the following formulae, in which R1, R2, R3 and X− are as defined above:
The process according to the invention can use monomers other than the monomer M. The macromolecular compound according to the invention may comprise units other than the units, derived from a monomer M.
These monomers may especially be polymerized at the same time, during the same step, as the monomer M (copolymerization). They may also or alternatively be polymerized during other polymerization steps, for example to obtain compounds of controlled architecture comprising several parts, for example block copolymers.
The other monomers and the units derived therefrom may especially be:
The properties and uses of the compounds according to the invention may be modulated by means of these other monomers or other units, especially using the monomers, their proportions and their place in the architecture of the compound, according to the above criteria. The monomers are often classified according to these criteria, and values relating to these criteria for the various monomers are usually tabulated and available in the literature.
As examples of potentially cationic monomers from which potentially cationic units may be derived, mention may be made of:
As examples of cationic monomers from which potentially cationic units may be derived, mention may be made of:
in which X− is an anion, preferably chloride or methyl sulfate.
As examples of hydrophilic neutral monomers from which hydrophilic neutral units may be derived, mention may be made of:
As examples of hydrophobic neutral monomers from which hydrophobic neutral units may be derived, mention may be made of:
As examples of anionic or potentially anionic monomers, from which anionic or potentially anionic units may be derived, mention may be made of:
As examples of zwitterionic monomers from which zwitterionic units A may be derived, mention may be made of:
Monomers other than the monomer M that are particularly advantageous are the following monomers:
The compound according to the invention comprises a macromolecular chain of controlled architecture. It may especially be a hybrid compound comprising an inorganic part, for example an inorganic particle such as a silica particle, to which are attached macromolecular chains, generally obtained by growth on the inorganic particle. According to one preferred embodiment, the compound is a polymer, preferably a copolymer of controlled architecture, constituted of macromolecular chains of controlled architecture, not comprising an inorganic part.
The macromolecular chains of controlled architecture may typically be obtained by means of one or more controlled radical polymerization steps, involving transfer groups of formula —S—SC—.
The macromolecular chains of controlled architecture may especially:
The compound, preferably a copolymer of controlled architecture, may especially have one of the following structures:
According to one particular embodiment, part A is derived from ethylenically unsaturated monomers.
These structures especially have in common the fact that they can be obtained by means of the process according to the invention. A person skilled in the art can determine the type of process that can be used and the useful sequences of steps. One of the steps may be the polymerization step P. Reference is also made to the “Processes” section hereinbelow.
According to one particular embodiment, the compound is a block copolymer, preferably a linear block copolymer, comprising at least one block A and at least one block B, preferably a diblock copolymer (block A)-(block B) or a triblock copolymer (block A)-(block B)-(block A) or (block B)-(block A)-(block B), in which:
It is mentioned that the triblock copolymers obtained via processes using three successive polymerization sequences are often described as copolymers containing blocks (block A)-(block B)-(block C). When the composition and the molecular mass of the third block C are substantially identical to the composition and molecular mass of the first block A (the amounts and proportions of (co)monomers being substantially identical), the triblock copolymers may be described as triblock copolymers A-B-A' or, by extension or simplification, as triblock copolymers A-B-A.
The macromolecular chains may, for example, have an average molar mass of between 0.1000 g/mol and 2 000 000 g/mol, often an average molar mass of between 2000 g/mol and 100 000 g/mol. This may be a theoretical average molar mass, calculated from the amounts of monomers used and of the optional transfer agents used, in a manner known to those skilled in the art. It may be a number-average molar mass, measured by steric exclusion chromatography (SEC).
Parts A and/or B, in which part B at least comprises units derived from the monomer M, may have an average molar mass of between 500 g/mol and 1 000 000 g/mol and often an average molar mass of between 1000 g/mol and 100 000 g/mol. This may be a theoretical average molar mass, calculated from the amounts of monomers used and of the optional transfer agents used, for the preparation of the part under consideration. It may be a number-average molar mass, measured by steric exclusion chromatography (SEC). The measured average molecular mass of a part obtained by polymerization subsequent to a preceding polymerization is defined as the average molar mass measured after the polymerization subsequent to which is deducted the average molar mass measured after the preceding polymerization.
The weight ratio between part A and part B, in which part B at least comprises units derived from the monomer M, may be, for example, between 1/100 and 100/1. It may be a weight ratio between the monomers used to generate part A and part B. It may be a weight ratio between the theoretical or measured average molar masses of part A and of part B.
By way for example, the compound may be a linear block copolymer of diblock type (block A)-(block B), of triblock type (block A)-(block B)-(block A) or of triblock type (block B)-(block A)-(block B), in which block B comprises units derived from the monomer M, having a theoretical or measured average molar mass of between 1000 g/mol and 2 000 000 g/mol, often an average molar mass of between 2000 g/mol and 100 000 g/mol. The block(s) A may especially be one (or more) block(s) with a theoretical or measured average molar mass of between 500 g/mol and 1 000 000 g/mol, often an average molar mass of between 1000 g/mol and 100 000 g/mol. The block(s) B may especially be one (or more) block(s) with a theoretical or measured average molar mass of between 500 g/mol and 1 000 000 g/mol, often an average molar mass of between 1000 g/mol and 100 000 g/mol. The weight ratio between the block(s) A and the block(s) B may especially be between 1/100 and 100/1.
The process according to the invention uses the polymerization step P described above. Depending on the compound to be prepared, the process may comprise other prior or subsequent steps.
During the polymerization step P, the monomer M preferably represents from 1% to 100% and preferably from 10% to 100% by number of the monomers used during the polymerization step P.
In addition, the process may comprise:
It is mentioned that the other polymerization step may constitute a step P if it uses the monomer M. In this case, it may be denoted, for example, as a polymerization step P′.
If successive polymerizations are performed, it is, however, preferred for the polymerization step P to be subsequent to a step not using monomer M, or using less than 50% by number and preferably less than 10% by number.
Steps for chemical modification of the macromolecular chains are directed toward adding to the chains functional groups, removing groups from the macromolecular chains or substituting groups of macromolecular chains. These groups may especially be borne by units derived from monomers or borne at the ends of a macromolecular chain. Such processes are known to those skilled in the art. Mention is made, for example, of total or partial hydrolysis steps, or total or partial crosslinking steps.
The deactivation of transfer groups borne by the macromolecular chains, and/or purification and/or destruction of by-products of the chemical modification and/or deactivation, may be performed. It may be a reaction for the purification or destruction of certain species, for example via processes of the type such as hydrolysis, oxidation, reduction, pyrolysis, ozonolysis or substitution. An oxidation step with hydrogen peroxide is particularly suitable for treating sulfur-bearing species. It is mentioned that some of these reactions or operations may take place totally or partially during a chemical modification step.
The polymerization step P uses a compound comprising a transfer group of formula —S—CS—. According to one embodiment, it is an inorganic compound, for example inorganic particles, on which are present transfer groups of formula S—CS—, these groups having been grafted, for example. According to one embodiment, it is a polymeric compound onto which have been grafted transfer groups of formula S—CS—. This embodiment is especially suited to the preparation of comb copolymers whose side chains comprise units derived from the monomer M, or block copolymers comprising a silicone block. According to one embodiment, it is a nonpolymeric transfer agent comprising a transfer group of formula —S—CS—. According to one embodiment, the compound comprising a transfer group of formula —S—CS— is a macromolecular compound obtained during a preceding polymerization step, which may have used a compound comprising a transfer group comprising a group of formula —S—CS—. Typically, the first polymerization step uses an inorganic compound on which the transfer groups are present, or a nonpolymeric transfer group comprising a transfer group of formula —S—CS—.
Transfer groups of formula —S—CS— and compounds comprising these groups, especially transfer agents, are known to those skilled in the art and are described in the literature. They may especially be selected according to their reactivity toward certain monomers and/or their solubility in the reaction medium.
The transfer group may especially comprise a group of formula —S—CS—Z— in which Z is an oxygen atom, a carbon atom, a sulfur atom, a phosphorus atom or a silicon atom, these atoms being, where appropriate, substituted so as to have a suitable valency.
Useful agents, groups or processes are especially described in the following documents:
Particularly useful transfer agents that may be mentioned include:
In the process according to the invention, these agents may be used during at least one polymerization step.
The polymerization step P uses a compound bearing or generating free radicals. According to one embodiment, it is a nonpolymeric initiating compound. Such compounds are known to those skilled in the art. According to another embodiment, the compound bearing or generating free radicals is present in a polymerization product from a preceding step. In this case, the use of an initiator is optional. In general, when several successive polymerization steps are used, it is preferred to add an amount of initiator in each step.
As examples of initiators that may be used, mention is made of:
They may be, for example, one of the following initiators:
For correct functioning, especially in terms of speed, of the polymerization step P, it is advantageous to work at relatively high monomer concentrations in the polymerization medium, preferably of at least 40% or even of at least 50% by weight. It is preferred to work at moderate temperature, for example between 30 and 70° C., typically at about 50° C.
The polymerization step P, and/or the other polymerization steps, may especially be performed by solution polymerization (for example in aqueous, alcoholic or hydroxy-alcoholic solution), or by bulk or emulsion polymerization. The polymerization step P may especially be performed in inverse emulsion, especially when the monomer M is DADMAC.
For example, for the preparation of block copolymers, it is possible to perform a first polymerization step in the presence of transfer groups to generate a first block, and then a second polymerization step (the transfer groups still being present) with a monomer composition that is different than that of the preceding step, to generate a second block, and optionally other polymerization steps, with monomer compositions different than those of the preceding step, to generate other blocks. The first step may be a step P using the monomer M, the second step may be a step P using the monomer M, and the other steps may be steps P using the monomer M.
Thus, according to one embodiment:
To obtain diblock copolymers (block A)-(block B), no polymerization steps other than steps a) and b) above are performed.
It is especially possible to prepare triblock copolymers A-B-A in two polymerization sequences, using agents comprising two transfer groups or agents comprising a transfer group allowing a transfer at each end of the group, for example a trithiocarbonate comprising a group of formula —S—CS—S—. In such processes, the blocks A are entirely identical, and block B generally comprises a central group that is different than the repeating units of block B. Mention of the presence of a central group within block B, noted, for example, as —X—, —X—Z′—X— or R′ hereinbelow, is often omitted for the sake of simplification.
Thus, triblock copolymers A-B-A may be prepared via the following process:
Triblock copolymers A-B-A may also be prepared via the following process:
Triblock copolymers A-B-A may also be prepared via the following process:
Concentration-gradient copolymers may be obtained via a polymerization step P during which the proportion of monomer M relative to the other monomers is gradually reduced.
Comb copolymers comprising a part B corresponding to the side chains may be obtained by means of a step P of polymerization of the monomer M or of a monomer mixture comprising the monomer M, in which the macromolecular chains are grown on transfer groups present (for example grafted) on a backbone A prepared beforehand. The backbone A may be a polymer derived from an ethylenically unsaturated monomer, or another backbone, for example a polysaccharide or a silicone.
Comb copolymers comprising a part B corresponding to the backbone may be obtained by means of a step P of polymerization of the monomer M or of a monomer mixture comprising the monomer M, followed by grafting or growth of the macromolecular chains corresponding to the part A, on units preferably derived from monomers other than the monomers M.
Star copolymers or star microgels comprising a part A and a part B may especially be obtained via “arm first” or “core first” processes, which are described especially for other monomers in documents WO 00/02939 (arm first) and WO 2004/014 535 (core first).
The “arm first” process involves a step of linear polymerization in the presence of ethylenically unsaturated monomers and of a compound comprising a transfer group of formula —S—CS—, followed by a step of formation of a core by polymerization in the presence of the product from the preceding polymerization step and of polyethylenically unsaturated monomers. The polymerization step P may be a step of linear polymerization and/or the core-forming step, the monomer M being used in at least one of the steps.
The “core first” process involves a step of forming a core by polymerization in the presence of a transfer agent comprising a transfer group of formula —S—CS— and of polyethylenically unsaturated monomers, followed by a step of linear polymerization in the presence of ethylenically unsaturated monomers and of the product from the preceding core-forming step. The polymerization step P may be the step of linear polymerization and/or the core-forming step, the monomer M being used in at least one of these steps.
The compounds comprising macromolecular chains according to the invention, and/or the compounds obtained or that may be obtained by means of the process according to the invention, may be used in many industrial sectors.
They may especially be used:
In these fields, they may be used as:
Other details or advantages of the invention may emerge in the light of the nonlimiting example that follows.
0.52 g of O-ethyl-S-(1-methoxycarbonylethyl)xanthate of formula (CH3CH(CO2CH3))S(C═S)OEt, 1.76 g of ethanol and 1.76 g of water are introduced at 30° C. into a 100 mL glass reactor equipped with a magnetic stirrer and a condensing column. The temperature of the solution is increased to 70° C. Once this temperature has been reached, 0.10 g of 4,4′-azobis(cyanovaleric acid) is introduced. Once this initiator has been introduced, 20 g of an aqueous acrylamide solution at 50% by weight are introduced over two hours. After one hour of introduction, a further 0.10 g of 4,4′-azobis(cyanovaleric acid) is introduced. The reaction is continued for 4 hours after the end of the introduction.
A sample of polymer is taken. Analysis of the product by high-performance liquid chromatography (HPLC) makes it possible to determine that all the acrylamide has reacted during the polymerization. An analysis by steric exclusion chromatography (SEC) with poly(ethylene oxide) relative calibration gives the following number-average molar mass and polydispersity index (Mw/Mn) values: Mn=1400 g/mol, Mw/Mn=1.40.
At the end of synthesis of the first block, the temperature is reduced to 50° C. Once this temperature has stabilized, a solution of 15.38 g of diallyldimethylammonium chloride (DADMAC) at 65% by weight in water is introduced, along with 146 mg of initiator V50 (2,2′-azobis(2-methylproprionamidine) dihydrochloride). The reaction is then maintained at this temperature for 8 hours. At the end of reaction, a sample is taken. 1H NMR analysis gives a DADMAC conversion equal to 73%. The Mn and Mw/Mn are measured by SEC in water: Mn=2800; Mw/Mn=1.27. The superposition of the two chromatograms of products A1 and A2 makes it possible to determine that the copolymer formed is of diblock nature. Specifically, the SEC chromatogram of step 1 is totally shifted toward the range of higher molecular masses at the end of step 2.
31.87 g of O-ethyl-S-(1-methoxycarbonylethyl)xanthate (CH3CHCO2CH3)S(C═S)OEt, 101.3 g of ethanol, 8.5 g of acrylic acid and 23.64 g of water are introduced at room temperature into a 2 L jacketed glass reactor equipped with a mechanical stirrer and a condensing column. The temperature of the solution is increased to 70° C. Once this temperature has been reached, 0.49 g of 4,4′-azobis(cyanovaleric acid) is introduced. Once this initiator has been introduced, a solution of 76.5 g of acrylic acid in 212.8 g of water is introduced over one hour. At the end of introduction, a further 0.49 g of 4,4′-azobis(cyanovaleric acid) is introduced. The reaction is continued for 3 hours after the end of the introduction.
A sample of polymer is taken. Analysis of the product by high-performance liquid chromatography (HPLC) makes it possible to determine that all the acrylic acid has reacted during the polymerization. An analysis by steric exclusion chromatography (SEC) with poly(ethylene oxide) relative calibration gives the following number-average molar mass (Mn) and polydispersity index (Mw/Mn) values: Mn=650 g/mol, Mw/Mn=1.60.
At the end of synthesis of the first block, the temperature is reduced to 65° C. Once this temperature has stabilized, a solution of 706 g of diallyldimethylammonium chloride (DADMAC) at 65% by weight in water is introduced, along with 4 g of initiator V50 (2,2′-azobis(2-methylproprionamidine) dihydrochloride). The reaction is then maintained at this temperature for 12 hours. After 4 hours and 8 hours of reaction, a further 4 g of initiator V50 are added each time to the reaction medium. At the end of reaction, a sample is taken. 1H NMR analysis gives a DADMAC conversion equal to 98.2%. The Mn and Mw/Mn are measured by SEC in water with a PDADMAC calibration curve: Mn=2500; Mw/Mn=1.50. The superposition of the two chromatograms of products A1 and A2 makes it possible to determine that the copolymer formed is of diblock nature. Specifically, the SEC chromatogram of step 1 is totally shifted toward the range of higher molecular masses at the end of step 2.
Number | Date | Country | Kind |
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06 05926 | Jun 2006 | FR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2007/056419 | 6/27/2007 | WO | 00 | 11/18/2009 |