CN1242389A

CN1242389A - Multipolymer thermoplastic elastomeric compound with improvement of filling, solubilisation and vulcanization

Info

Publication number: CN1242389A
Application number: CN 98115829
Authority: CN
Inventors: 朝克
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-07-17
Filing date: 1998-07-17
Publication date: 2000-01-26

Abstract

The multi-component thermoplastic elastomer composiis a high polymer chemical composite material, belonging to a thermplastic rubber-plastics alloy (TPV or TPV-S) filled with polymer blend modified material and solubilized, aimed at producing low-cost new product by using general cheap materials and matched modification process. It is characterized by that it selects and uses NR + BR/PP, PE, EVA and their combination to formthe specific elastomer type material, and uses carboxylic ester, rare earth and bentonite to make reinforcing and filling instead of white carbon black to improve its activity and properties, and prepares the esterification adjuvant modified by maleic anhydride, and uses one to improve the compatibility and structural property of said material, so that it establishes the effective practibility of TPV-S method.

Description

Multicomponent thermoplastic elastomer composition with improved filling, solubilization and vulcanization

On the basis of the modification experiment of thermoplastic materials such as SBS and the like, by referring to the research of foreign rubber-plastic alloy elastomer materials and through the combined experiment research of different multi-element (more than three elements) blends with special purposes, the key research is to intensively research the ternary to quinary combined thermoplastic TPV and TRV-S materials which take NR + BR and rubber as base materials and take PE, PP, EVA and the combination thereof as alloy materials. The invention tries to solve the problem of the intermiscibility reinforcing filling material of the blending process; compared with the prior art, the three independent inventions and the three independent processes are found to have good improvement on the mechanical and physical properties of the multi-element blend.

The invention relates to a high molecular chemical composite material, which belongs to thermoplastic rubber-plastic alloy (TPV and TPV-S dynamic-static method) materials filled and solubilized by a blending type modified material. The method comprises four independent researches, wherein firstly, a selected multi-element (ternary-quinary) special blend has unique innovation and testability in the aspects of material selection and combination blending thereof; secondly, the reinforcement, filling material and manufacturing process of compatible carboxylate rare earth bentonite are independently completed, and a filling contrast experiment is performed, so that the performance is improved, the cost is reduced, and the heat resistance, the oxygen resistance and the activity of the alloy material are increased; thirdly, independently completing the manufacturing process and method of a solubilizing esterification tackifying and plasticizing intermediate, and being used for improving the material performance and high-temperature denaturation problem in multi-element high-temperature dynamic crosslinking; and fourthly, the influence and the comparison of a dynamic method and a dynamic and static matching method on the structure and the performance of the material are compensated and tested, and the method is improved. The invention of this application belongs to the thirty th patent law and the thirty-fifth patent law implementation rules which refer to two or more inventions making a general inventive concept.

After 80 years, the industrialized thermoplastic elastomer mainly comprises the following components: styrenes, olefins, polyesters, polyamides, and the like. The olefine is a blended thermoplastic elastomer, and compared with the synthetic method, the olefine has the advantages of simple process, less equipment investment, low cost, easy performance adjustment and the like, and is increased at the development speed of 2-3 times of the rubber industry. TPV (thermoplastic vulcanate) thermoplastic dynamic vulcanization is a process in which a vulcanization reaction is generated by a vulcanizing agent under the action of dynamic shearing force when rubber and resin are melt-mixed. The thermoplastic vulcanizate was first prepared in 1962 by Gessele, Coran et al, the end of the 70 s, and EPDM/PP blends were prepared by Monsanto, USA. In recent years, a batch of novel TPV is developed and applied for a plurality of patents, and the TPV is stepped into a new field of industrial materials.

A series of blending type TPE technologies [1][2]are developed and researched in China in succession since 87 years, most of the blending type TPE technologies are binary alloys, the researches are only limited to the researches on the shapes, structures and performances of main resin and elastomer materials, and the effects of carbon black and white carbon black which have the traditional reinforcing effect on TPV are not considered to have obvious effects [3]. The novelty of the invention lies in the economic aspect at first, and new compensation tests are made in the aspects of reducing the cost, increasing the material activity and searching for a substitute reinforcing material; secondly, the unique and used materials are selected. The TPE with the multi-component rubber has not been researched much in the past, and the combined purpose is to improve the alloy performance on one hand and is valuable from the aspect of cost on the other hand. And thirdly, the phenomena of uneven plasticization (processing condition difference), bulkiness, viscosity loss and the like of the blended rubber and the resin alloy in a high-temperature crosslinking state are modified, a solubilizing esterification tackifying and plasticizing complexing agent is prepared, and the addition contrast effect is very obvious. In addition, the dynamic TPV and dynamic shearing-static vulcanization two-step method is compensated, and the performance of the two-step TPV-S is superior to that of the dynamic vulcanization method and depends on the pressure. The common mechanical shearing equipment is difficult to have static vulcanization pressure and has poor vulcanization effect.

Through the journal of rubber industry in 89-98 years; journal of elastomer 91-97 years; journal of synthetic rubber industry from 92 years to 95 years; journal of Polymer Material, 92-98 years, comprehensive review and search of Chinese patents in the specialty and Chinese countries, detail review of elastomer mechanical modification, modern rubber technology and handbook of rubber industry, in 91-95 years, 95-97 years, journal of Polymer Material, etc., it can be determined that the thermoplastic elastomers applied abroad at present are graft-polymerized, and the blended TPV at present is found in EPDM/PP or PVC 4][5, SBR/PVC 6, PVC/SBR/NBR-26[7], SBR/PE [8], NR/PE or PP [9], PVC/NBR/HDPE [10], NBR/PP [11], SBR + NR/LDPE [12], SBR/LDPE [13], SBR/pp [14], SBR + BR/LDPE [15], BR/(L.H.LL) PE [16], and the like. For the experiments with the elastomer combinations of the present invention: NR + BR/PP, NR + BR/PE, NR + BR/PP + PE, NR + BR/PE + PP + EVA, NR + BR/PE + EVA, according to the corresponding reference comparison, in addition the above-mentioned combination has all added modified filler and complexing agent, made the comparative experiment.

The invention aims to prepare thermoplastic elastomers with wide material source, low cost and various purposes. The effect and the advantage are shown as follows: 1. economy of material selection. The materials such as block SBS, SBIS and the like have limited sources, are imported abroad more and have high price exclusivity. The natural rubber and the butadiene rubber are selected to have wide sources and low price, the NR/BR tested by the invention is 50/50 or 25/75, the price cost is low, and the total rubber/plastic is 70/30-60/40. 2. The application is diversified. The combination of a plurality of different resins can obtain the elastomers with different uses and soft grades and medium-hard grades, and the hardness ranges are as follows: 56A-80A, which is the same as the rubber and plastic disclosed so far, and has lower hardness than the elastomer, and the elongation at break is 400-. 3. The material has composite property. In the dynamically crosslinked TPE, the traditional reinforcing materials of carbon black and white carbon black are generally considered to have no obvious effect on TPV, and the invention starts with the low-cost filling of the reinforcing material. The substitute material with stronger activity is searched, carboxylate rare earth modified bentonite is selected, a product or complex structure is formed between crystals, the product is similar to white carbon black, the activity is higher, the material can be used as a novel filling and reinforcing material of rubber materials, and the elasticity is good. On one hand, the cost is only 1/3 of the white carbon black, the compatibility is good, and the mixture shows good luster and stiffness compared with the bentonite material which is not added or only added with surface active treatment from low-temperature open mixing and high-temperature mixing. On the other hand, it can improve the heat-resisting stability and the oxygen resistance, and also has the functions of heat-resisting degradation and light aging resistance for PVC plastics, and the carboxylate rare earth and the complex compound generated between the bentonite crystal can play the role, and replace the organotin heat stabilizer [17][18], and is one of independent products. 4. The process innovation is good. It is theorized that TPV elastomers are readily dispersed in the "sea" of resin in the form of "islands" when crosslinked under high shear conditions due to the high viscosity of the gum. It has also been demonstrated that static methods can still give rise to the same structures and that performance is superior to dynamic structures [19]. The invention tests that the multi-element blend is dynamically sheared at a higher temperature under the action of an S/accelerating and S/peroxide crosslinking system, because of the existence of rare earth complex, the multi-element blend has thermal stability and good processability, the alloy has crosslinking viscoelasticity, a certain phase state distribution is realized, a compatibilization type tackifying and a plasticizing agent are added to facilitate the glue to form an island phase and refine particles, and high-temperature, pressurization and rapid vulcanization (1-3 minutes) are adopted for the second time, so that the effect is better. The dynamic shear extrusion effect (compression ratio 3.5) is slightly inferior to the two-step moving and static method. The elongation at break by the dynamic method is lower.

(I) Experimental Material combination (Main)

The natural rubber (3# smoked sheet), the cis-polybutadiene rubber, the linear low-density polyethylene, the polypropylene powder, the EVA, the carboxylate rare earth bentonite, the miscible tackifying plasticizer and the S/accelerator (S/peroxide) are combined:

NB-E30-40 NR + BR60-70 (50/50; 25/75)/PE30-40+ others

NB-P30-40 NR + BR60-70 (50/50; 25/75)/PP30-40+ others

NB-EP30-40 NR + BR60-70 (50/50; 25/75)/PP + PE (30-40) + others

NB-EA30-40 NR + BR60-70 (50/50; 25/75)/PE + EVA (34-40) + others

NB-EPA34-42 NR + BR58-66 (50/50; 25/75)/PP + PE + EVA (34-42) + others

Meanwhile, compared with partial experiments of not modifying and only surface activating treatment of bentonite filling, the modified filler is proved to have a reinforcing effect, the elongation at break is notinfluenced, and only the hardness and the 300 percent definite elongation are improved.

(II) a processing technology:

1. dynamic method. After the alloy material and the filling material are mixed and melted, the mixture is subjected to high-temperature banburying shearing or high-temperature extrusion shearing with master batch rubber added with the S/accelerator, and is vulcanized in place. The process shown in figure 1 is a two-step banburying or extrusion process.

2. The static and dynamic methods. The mixed alloy material is mixed with master batch glue, and is subjected to dynamic shearing when the temperature is raised to 10-15 ℃ above the melting point of the resin, so that cross-linking viscoelasticity appears, island phase distribution of the glue is realized, and then static full cross-linking is carried out (shown in the attached figure 2).

(III) carboxylate rare earth bentonite reinforcing filler

1. The process comprises the following steps: removing impurities from bentonite solution with dilute acid, activating with rare earth, and reacting with carboxylic acid under basic condition to obtain intercrystalline product (shown in figure 3).

2. Activation of<A>: when RE is present⁺³High-price RE is absorbed by water entering montmorillonite intercrystalline and interlaminar⁺³Under the action of ion polarization electric field, the dissociation degree is several orders of magnitude greater than that of common water, so that the ligand is located in RE⁺³The surrounding water molecules become acidic OH groups and a new Bronsted acid center is generated [20]]

Simultaneously removing impurities in the bentonite layer by acid liquorto generate NaCI and CaCl₂Iso-reaction<II>: in the presence of alkali (NaOH)

The following reaction occurs after the addition of the carboxylic acid.

。

……

(IV) solubilizing esterified plasticising and viscosity increasing agent

1. The process comprises the following steps: heating maleic anhydride, melt reacting with abietic acid, adding alcohol, esterifying, and dehydrating (shown in figure 4)

2. Reaction of<A> Reaction of<II>

Excess of

……

Claims

The invention discloses a multi-element thermoplastic elastomer combination with filling, solubilization and vulcanization improvement, which is a blend type modified multi-element thermoplastic elastomer (TPV or TPV-S) taking NR and BR as a combined rubber and PE, PP, EVA and the combination thereof as an alloy. The rubber phase is vulcanized in situ under the action of high-temperature dynamic shearing force, is dispersed in the resin 'sea' in the form of 'islands', and has the characteristic of melt flow forming, so that the rubber phase is called thermoplastic elastomer (TPV).

The invention relates to a special elastomer (carboxylate rare earth bentonite, solubilizing tackifying and plasticizing complexing agent, rubber and plastic alloy material combination and method, dynamic moderate vulcanization-static vulcanization method) formed by technically correlating three independent materials and combination thereof and improvement of a processing method. Meets the characteristics of the second clause of thirty-fifth patent law enforcement rules, and can respectively put forward independent patent claims.

1. Claims for carboxylate rare earth bentonites. The technical characteristics of the invention are thatThe rare earth strengthens the esterification of carboxylic acid by activated bentonite. The good intermiscibility and intercrystalline activity of the rare earth complex with the rubber are utilized to replace the traditional carbon black, especially white carbon black, as a filling and reinforcing material, and the heat resistance stability and the processability of the rubber-plastic alloy can be improved. Its whole technological scheme is characterized by that it uses bentonite as main filling material, and uses esterification to produce catalytic medium, after having been dissolved in water, it is expanded, and uses trace (HCI: 3%) to remove impurity, and activates, and adds RECI₃Then the crystal is polarized between crystals, water molecules are strongly ionized to be OH groups, and the OH groups are coordinated on RE⁺³The surrounding generates:

under the condition of adding alkali NaOH, the catalyst can generate ester with carboxylic acid

According to different hydrolysis degrees, a monocarboxylic ester rare earth and dicarboxylic ester rare earth compound is generated, and the filler is a greasy filler. The carboxylic acid adopted by the invention is stearic acid C₁₇H₃₅COOH. The intergranular catalytic product is (C)₁₇H₃₅COO)₂RE, (OH) and (C)₁₇H₃₅COO)RE(OH)₂。

According to the above, the independent claim is for carboxylic acid or C₁₇H₃₅COOH, bentonite, RECL₃The modified material is prepared by using HCL active treatment and NaOH hydrolysis esterification as well as the principle and the process for preparing the modified material, and the product produced and prepared by the principle and the process is also covered by 'carboxylic acid or stearic acid esterified rare earth bentonite' or 'modified bentonite' with the substance contentSoil'
2. Claims for solubilized esterified tackifying, plasticizing agents. The independent invention is used as the contribution to the whole technology for improving the mixing and dissolving, has the plasticizing and tackifying effects, and is technically characterized in that the maleic anhydride and the abietic acid are used for melting reaction, and then are esterified by the polyalcohol or the ethanol (such as generating the ethyl maleate), the compound has the tackifying, non-drying and plasticizing effects, improves the intercrystalline compatibility of an alloy body, and is particularly suitable for the modification of a multi-element material. The reaction principle and the manufacturing process are as follows:

1)、

2)、

usually a slight excess of maleic anhydride

The independent claim of the principle and process for preparing the volume-increasing esterified viscosity-increasing plasticizer from maleic anhydride, pinoresinoic acid, polyol and alcohol is disclosed. The products obtained in this way must not be produced, sold or used in the process of a processor without permission.
3. The improvement of TPV-S (dynamic-static matching) method.

TPV technology is a modern mature technology, and a plurality of products are produced. The improved technological characteristic of the method is that based on the original TPV processing technology, the sea-island structure of dynamic plastic-rubber phase distribution is researched, on one hand, the high-temperature shearing vulcanization can be realized in situ, and simultaneously, the phase distribution can be realized in two steps. Firstly, the 'alloy' material is mixed and melted, then is designed and processed under the coordination of a specific vulcanization system and a coordination aid (from the consideration of scorching prevention), and is dynamically sheared around the melting temperature of a resin phase to realize viscosity change or realize an island phase distributed by a rubber phase tackifying aid. Then the static forming is carried out at high temperature, pressurization and rapid forming (1-3 minutes) to meet the process requirements, and the performance is superior to that of dynamic shearing vulcanization after the static forming.

The independent claim for improvement of the TPV-S processing method lies in the exclusivity of the technology of producing TPE by using the dynamic and static two-step cooperation method or the corresponding product produced by using the method.
4. Claims are made to products formed from elastomeric materials and combinations thereof. The invention selects NR + BR (50/50, 25/75) uniquely, selects PE, PP, EVA and the combination thereof as alloy, and forms the combination of dynamic TPV and dynamic-static TPV-S thermoplastic elastomer under the coordination of S/accelerating and S/peroxide vulcanization system. The claim is characterized by a combination of nr.br blend glue with a three to five membered alloy of pe.pp.eva comprising:

NR + BR 60-70/PE: 30-40+ other auxiliary agents NB-E30-40

NR + BR 60-70/PP 30-40+ other NB-P30-40

NR + BR 60-70/PP + PE: 30-40+ other NB-EP30-40

NB + BR 60-70/PE + EVA: 30-40+ other NB-EA30-40

NB + BR: 58-66/PP + PE + EVA: 34-42+ other NB-EPA34-42
5. A process for preparing the multi-element thermoplastic elastomer filled with carboxylate-type RE bentonite and the compatibilizer-type modifier.

Except for the independent claims 1, 2, 3 and 4, the independent claims 1 and 2 are combined according to the required proportion, and the products of the composite thermoplastic elastomer are produced by the method and the material according to the items 3 and 4, or the same process and method are used, and the characteristics of the claims are included.