Patent Application
20100261845
The subject of the present invention relates to the low molecular weight compatibilizing additive package having further advantageous effects, which improves the compatibility of different thermoplastic and/or thermosetting polymers and/or fillings, functional additives just as composites containing natural and/or artificial strengthening fibres, and relates to its preparation and application processes.
In the last decades it has been typical in different industries to replace metal structural materials produced with high energy consumption by plastic materials. Accordingly plastic composites with better and better mechanical and chemical properties have been developed. Nowadays various additives are used to fulfil various requirements of products in these composites as filling and colouring materials, antioxidants, UV stabilizers, flame retardants, plasticizers and strengthening fibres, etc. Besides it is frequently required to use mixtures of polymers chemically different in structure. In the last two decades numerous compatibility improving, i.e compatibilizing additives have been developed for the production of such multi-component composites to promote compatibility of several types of the so called back-bone polymers and other components, e.g. additives, fibres, and filling materials containing polar groups, etc. (U.S. Pat. No. 5,959,032).
Generally the compatibilizing additives are high or low molecular weight polymers having similar structure to the so called back-bone polymer giving the main component of the composite that are functionalized by polar compounds, which can physically and chemically interact with the different kinds of components of the composites through their polar and apolar groups, providing the required processing and mechanical properties.
According to processes producing the known compatibilizing additives (U.S. Pat. No. 5,414,081), generally so called back-bone polymers are used as raw material that are of high molecular weight (
During the preparation of the compatibilizing additives functional groups were formed on the chains of the above mentioned polymers by reaction with different chemical reagents, which could interact with polymer molecules containing similar kind of chemical groups in significant ratio.
At first polymer functionalization was realized by radical initiated chlorination or methods based on oxidation by oxygen or hydrogen-peroxide, which were used to produce chlorinated polyethylene and either epoxydated or oxydated polyolefins. Disadvantages of that kind of processes are the low thermal stability of chlorine containing polymers mixed into the final product, and the formation of significant amounts of toxic hydrochloric acid during thermal decomposition. The resin type materials obtained in the oxidative processes were often corrosive and it was hard to reproduce them, their structure being far too complicated, composed of various functional groups. Therefore in further processes with radical or thermal initiated reactions, especially for grafting of back-bone polymers, other reagents were used as unsaturated carboxylic acids, e.g. maleic acid, fumaric acid, acrylic acid, methacrylic acid or their anhydrides, or chlorides or bromides of unsaturated acids, e.g. vinyl benzyl chloride, vinyl benzyl bromide, or unsaturated carboxylic esters as alkyl acrylate or alkyl methacrylate. There are numerous processes among the listed ones, which use maleic acid as acidic reagent (U.S. Pat. No. 5,959,032).
Efforts were made to improve the compatibility of polymers containing acidic functional groups to polymers containing mainly apolar or basic groups, as e.g. polyamides and other apolar polymers (U.S. Pat. No. 6,451,919).
H. Farah at all (U.S. Pat. No. 6,469,099) produced hydrocarbon polymers containing amine reactive groups to improve compatibility of polyurethanes and polymers containing carboxylic-, or hydroxyl functional groups with filling materials or strengthening fibre materials, apolar polymers or other apolar additives, or other components. Compatibilizing additives containing basic functional groups are obtained by reacting these polymers with alkyl amines, polyamines, hydroxyl amines and polyether amines, or polyether amides,
For commercial production of high molecular weight compatibilizing additives the twin-screw, the so called reactive extrusion, traditionally used mainly in polymer processing were applied (U.S. Pat. No. 6,469,099), whereby generally 5-10%, but at most 40% conversion referred to the back-bone polymer could be realised depending on the severity of conditions. The non-reacted polymers are mixed and dissolved into the composites that might have more or less influence on the properties of the end-product depending on the type of the polymer. As a result of functionalization reactions the functional groups are linked to the back-bone polymer chain in statistical distribution. Such products with compatibilizing effect can be directly used for polymer composite preparation, or can be reacted for building the necessary functional group structure with low molecular weight basic or acidic compounds during preparation of polymer composites or further reactive extrusion.
S. Moriya at all (EP 1,275,670 A1) prepared compatibilizer with high chemical and mechanical stability and significant improving effect on processing and application properties from C2-C20 olefins (
Compatibilizing additives are used in master mixtures or directly, generally in 3-40%, preferably in 2-10% concentration by the usual mixing technology for polymer composites. A properly directed orientation of the compatibilizing additive takes place in the melt phase, resulting in the formation of transient films bonded chemically or physically to the surface of polymers with different chemical characteristics dispersed in each other, and on the surface of other components assuring compact coordination and cohesion.
According to our research and development work in this field it was discovered, that the application of the known, traditional compatibilizers involves the following drawbacks:
During our research and development work on surface active polymers it was concluded, that by selective grafting of α-olefins of high reactivity having an average carbon number between C20-C40, preferably C22-C36, or of a hydrocarbon polymer containing more than 80% α-olefin and of an average molecular weight significantly lower than usual (
Component “A”: According to our invention the compatibilizing additive package for different types of plastic and/or rubber composites contains at least 45-97% of polar compounds consisting of an apolar hydrocarbon group (APG) and a polar group (POLG) having a number average molecule weight
Component “B”: According to our invention the compatibilizing additive package contains reactive vegetable fatty acid and/or fatty acid ester in 1-30% concentration, which contains in structure per molecule at least one olefinic double bond, or functional groups for ester and/or amide bonds as e.g. carboxylic-, acidic anhydride-, or hydroxyl-, amino-, imino groups, and by reacting with other reagents and/or component “A”, chemical bonds are formed and so the flexibility and mechanical strength of such additive containing disperse composite can be significantly improved. The proposed mass ratio of components “A” and “B” in the compatibilizing additive package (A/B) is 5-90 and preferably 15-50. In addition the compatibilizing additive package may contain other known additives, preferably in 0-40%, too, improving utilization properties as e.g. antioxidants, corrosion inhibitors, flame retardants, colour stabilizers, colouring materials, plastifiers, and inorganic and organic fillings, and dispersed strengthening fibres or nanotubes.
The preparation of Component “A” by this invention takes place in one or two main steps. In the first step unsaturated hydrocarbon raw material containing double bonds in α-position in more than 80% is grafted with a copolymer containing maleic anhydride and another comonomer having olefinic double bonds in its structure. During this reaction α-olefins having C20-C40, preferably C22-C36 average carbon number, or their mixture, or α-olefins with 3-8 carbon number, diolefins, or other homo and/or copolymers of aliphatic or aromatic hydrocarbon monomers containing olefinic double bonds, preferably polyisobuthylene in 20-75% concentration are applied. The reagents are dissolved in a hydrocarbon liquid, with a boiling point preferably at most 160° C., then the solution is heated to 110-160° C. and further reacted during 2-10 hours with maleic anhydride, and a C4-C16 comonomer containing olefinic double bonds, or with their mixture, by continuous or batch feeding of comonomers, within reaction conditions promoting the formation of alternating chain structure, in the presence of 3-15% of an organic peroxide initiator related to maleic anhydride, as e.g. di-tert-butyl peroxide, benzoyl-peroxide, cumene hydrogen peroxide, tert-butyl perbenzoate, etc. The next step is the boiling out of the volatile solvent and the unreacted monomers from the reaction mixture in vacuum between 200-320° C., then after cooling the acid number of the product is measured. On the basis of the carboxylic group concentration calculated from the acid number the proposed application concentration of the compatibilizing additive is determined. The structure of the hydrocarbon product grafted with the resulted copolymer was identified by FTIR, and proton NMR, or C13 NMR, and GPC analyses:
where: R=aliphatic hydrocarbon group (APG), which can be a C18-C40 α-olefin, or mixtures of such olefins, or a C3-C8 α-olefin, or the homo or copolymer of other hydrocarbon monomers containing olefinic double bonds with a number average molecular weight of less than 10000, preferably under 3000.
X, Y═C2-16 aliphatic or aromatic hydrocarbon group or H
n>1, average number of molecular parts containing polar groups bonded to group R.
Component “A” with strong acidic character is applied for improving the compatibility of polymers containing mainly hydroxyl or basic groups, and apolar hydrocarbon polymers. In case of polymers or fillers containing acidic or neutral groups, further chemical conversion of the carboxylic groups of the above described product is necessary. During the above process the compound described by general formula I is reacted for 2-10 hours in 10-70% hydrocarbon having an average boiling point of at least 150° C., preferably in an aromatic hydrocarbon solvent, in the presence of an acidic or basic catalyst in the 110-180° C. temperature range, or without any catalyst, with a molar ratio of 0.2-1.0 calculated for free carboxylic groups with various reagents, preferably straight or branched C3-C26 α-alcohol, alkanol amines, C3-C26 alkyl amines, polyalkylene polyamines, amino piperazine, polyalkylene glycols, polyether amines, or aromatic alcohols, or aromatic amines, or their mixtures; as a result ester-, amide-, ester- amide-, succinimide-, or polysuccinimide type end-product is prepared, which contains at least one free —OH or —NH2, or —NH polar end groups per molecule, limitedly soluble or insoluble in aliphatic hydrocarbons, from which the solvent and the unreacted components can be boiled out between 100-350° C. in vacuum.
Component “B” is a reaction product of a C16-C24 fatty acid and/or fatty acid ester containing at least one olefinic double bond grafted with maleic anhydride, or copolymers of maleic anhydride and C4-C24 aliphatic olefins, or aromatic hydrocarbon monomers containing olefinic double bonds, or its partly neutralized reaction product obtained by reacting with further reagents having a number average molecular weight less than
According to our experiences the additive package having high active material content and lower average molecular weight than usual in such packages, in which component “A” is characterised by containing alternating copolymer chain structure grafted to the end of the apolar hydrocarbon chain, i.e. the additive molecule in one part contains concentrated polar groups, have resulted in higher surface active effect than achieved previously. As a result, it is applied at significantly lower concentration levels as the commercial reference additive, and such extrudable polymer composites are also successfully manufactured, which have not been mentioned in the literature so far.
It is assumed, that additives by the present invention that are strongly polar and of low molecular weight can quickly disperse at the processing temperature of plastic materials because of their higher diffusivity in high molecular weight polymers as well, and by physical or chemical interactions can create good bonding surface layers on polymer/polymer or polymer/solid dispersed phase surfaces, and through their free functional groups they are able to create chemical bonds with each other, or with other known plastic components with cross linking properties, or fillings having stabilizing effect on the polymer composite structure. Besides, owing to their high active material content only a low amount of unreacted diluting component is taken to the composite, which does not deteriorate considerably the mechanical properties of the composite.
During the processing of the composite in the state of plastic melt component “B” shows advantageous slip effect, while its reactive functional groups react with component “A” resulting in the post growth of the average molecular weight of the composite, and the formation of bonds between phases dispersed in each other.
According to our experiments it can be stated, that compatibilizing additives by this invention have got other side effects besides the compatibility assuring main function, like adhesion improving, plastifying (slip), mechanical properties improving, promoting dimensional stability and dyeability.
The utilization advantages of the compatibilizing additive package according to this invention are described in the following manufacturing and application examples.
In a 1 dm3 volume four necked glass stirring vessel 300 g (1 mol) of a commercial C24 α-olefin (α-olefin content is 98%) is dissolved in 1:1 mass ratio in toluene, then the mixture is heated to 105° C. 128 g (1.3 mol) of maleic anhydride (MA), 135 g (1.3 mol) of styrene and 13 g of benzoyl peroxide are fed into the mixture in 13 equal parts during 2 hours, under stirring and N2 gas bubbling, with 10 minutes break periods. After 20 minutes post reaction the unreacted volatile components are boiled out of the reaction mixture at 250° C. and 2 kPa pressure, and N2 gas bubbling. The acid number of the intermediate obtained is 220 mg KOH/g and the average coupling ratio calculated by mass balance is 1.1 for maleic anhydride related to the α-olefin raw material. In the second step of manufacturing 300 g of intermediate is dissolved in a similar 1 dm3 volume glass vessel in 150 g of xylene at 120° C. while mixing, and a mixture of 0.75 times mol ratio of n-decyl-alcohol (164 g) calculated from the gmol weight of carboxylic groups determined from the acid number of the intermediate, and of 0.25 times mol ratio of diethylene glycol (31 g) is fed to the solution in 30 minutes, then the reaction mixture is heated to 170° C. and refluxed for 8 hours while continuously boiling out the reaction water. The ceasing of the formation of reaction water indicates the end of the estering process. After that the volatile solvent and unreacted components are boiled out of the reaction mixture at 280° C. and 2 kPa pressure, by N2 gas bubbling. The esterification of carboxylic groups of the maleic acid polymerized into the intermediate product chain in component “A” is detected by the shifts of FTIR absorption peaks of carbonyl groups C═O at wavelengths of 1880 cm−1 and 1775 cm−1.
The average number of polar succinic anhydride rings polymerized to the side chain of olefin in the intermediate manufactured in the first step (coupling ratio, CR), is calculated by the following equation based on the mass balance of manufacturing and product analysis data:
The mass ratio of the apolar (APG) and polar groups (POLG) in the molecules is calculated by the following equation:
In a 1 dm3 volume four necked glass stirring vessel 300 g (1 mol) of rape-seed fatty acid methyl ester with high oleic acid content (over 80%) with regard to its fatty acid composition is dissolved in 120 g of xylene, then 138 g (1.4 mol) of maleic anhydride and 14 g of di-tert-buthyl-peroxyde are continuously added during 4 hours into the mixture heated to 145° C. After 1.5 hours post reaction the grafting process is finished, and the volatile and unreacted monomers are boiled out of the reaction mixture. 150 g of the manufactured intermediate, characterized by an acid number of 360 mg KOH/g, is weighed in the previous 1 dm3 volume four necked glass stirring vessel, and dissolved in 100 g of toluene, then reacted with n-octyl-amine of an amount related to the carboxylic groups in 0.25 times mol ratio, at 150° C. for 4 hours with continuous boiling out and separation of the reaction water, then the volatile components are boiled out of the reaction mixture at 150° C. and 10 kPa pressure. The acid number of the manufactured end-product is 185 mg KOH/g.
Into a 2 dm3 volume enamelled autoclave supplied with mixer 500 g of C9-C12 aromatic solution (Aromatol), 1000 g (1 mol) of polyisobuthylene (FIB) of high reactivity, containing more than 80% terminal double bonds are fed, then heated to 150° C. with N2 gas bubbling. Then 247 g of maleic anhydride (2.5 mol), and 630 g (2.5 mol) of n-octadecene, and 2 g of tert-buthyl peroxide are fed into the autoclave within 1 hour in 2-2 equal parts; after finishing the feeding the reaction mixture is boiled out during an additional 4 hours mixing at 150° C. and 5 kPa pressure. The acid number of the manufactured intermediate is 160 mg KOH/g and the average coupling ratio (maleic anhydride rings grafted per PIB molecules) is 2.2. 300 g of the manufactured intermediate is poured into a 1 dm3 glass vessel, heated to 120° C. while stirring, and during 10-10 minutes 46 g of benzyl alcohol and 44 g of diethylene triamine are fed to it. To promote esterification and amide formation reactions, the reaction mixture is heated to 180° C. and refluxed for 6 hours, then the unreacted components and the solvent are boiled out of the reaction mixture at 240° C. and 3 kPa pressure. The nitrogen content of the end-product manufactured in this way is 6.4%.
2475 g of acrylnitrile butadiene styrene (ABS) copolymer (Melt Flow Index MFI=34 ml/10 min, 220° C. temperature, 10 kg load) and 2475 g of high-impact polystyrene (MFI=7, 5-11 ml/10 min, 200° C. temperature, 5 kg load) from process waste are mixed in a speed mixer with 50 g of the compatibilizing additive package containing 40 g of component “A” by Example III, 7 g of component “B” by Example II, and 3 g of a commercial styrene-butadiene-styrene (SBS) elastomer with plastifying effect. The mixture is fed into a moulding machine supplied with tool for standard specimen production.
A 10 mass percent stock solution is prepared from 10 g of a mixture of component “A” by Example I and component “B” by Example II in a mass ratio of 37:3, and 90 g of xylene; 20 g of carbon fibre is dipped into this solution and the solvent is removed at 120° C. from the carbon fibre. The carbon fibre impregnated in this way and previously cut is mixed with 400 g of HDPE waste polyethylene by moulding, and then a sheet is made by hot pressing for specimen cutting.
Practical advantages of the additive packages according to this invention described in general examples I-V are presented through definite implementation examples (Tables 1-4). Reagents and their properties are summarized in Table 1 for component “A”, and in Table 2 for component “B” of the compatibilizing additive packages. The composition of additive packages is given in Table 3, while Table 4 contains the composition and mechanical properties of the plastic composites made with additive packages of Table 3. Results of measurements with standard test methods and specimens certify that plastic composites prepared with compatibilizing additives according to this invention had better mechanical and elastic properties by 5-100% —compared to specimens produced without any additive or with commercial additives.
Significant improvement of application properties have been achieved for both thermoplastic plastomers (PP, HDPE, etc.) and elastomer (PVA), and thermosetting composites.
| Number | Date | Country | Kind |
|---|---|---|---|
| P0700680 | Oct 2007 | HU | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/HU08/00123 | 10/14/2008 | WO | 00 | 6/3/2010 |
