Preparation method of high-barrier bio-based polyester PEF filled IIR composite material

Abstract

The invention relates to a preparation method of a high-barrier bio-based polyester PEF filled IIR composite material, and the preparation method of the high-barrier bio-based polyester PEF filled IIR composite material comprises the following steps: mixing 100 parts by weight of IIR and 2.5-10 phr of PEF to obtain a uniformly mixed rubber compound; and then adding zinc oxide, stearic acid, an accelerant TMTD, an accelerant M and sulfur to perform vulcanization treatment on the rubber compound to obtain the composite material PEF / IIR. The preparation method of the high-barrier bio-based polyester PEF filled IIR composite material adopts PEF to modify IIR, and has the advantages of IIR vulcanization promotion, small PEF dosage, good compatibility, good PEF dispersibility, good gas barrier property, mechanical property improvement and the like.

Description

Technical Field

[0001] The invention relates to the field of materials, and in particular to a method for preparing a high-barrier bio-based polyester PEF-filled IIR composite material. Background Art

[0002] Butyl rubber (IIR) is obtained by cationic polymerization of isobutylene and a small amount of isoprene. It has good thermal stability, chemical stability and gas barrier properties and is widely used in tire inner tubes and medical plugs. With the rapid development of the domestic automobile industry, IIR, as one of the important raw materials for tire production, has an increasing consumption year by year. However, it has defects such as slow vulcanization rate and poor compatibility with other elastomers in production, and needs to be modified.

[0003] At present, the mechanical properties of IIR can be improved by modifying it with inorganic rigid particles such as carbon nanotubes (CNT), graphene oxide (GO), and montmorillonite (MMT) as reinforcing fillers. However, the reinforcement effect is limited due to the weak interaction between IIR and inorganic fillers. In addition, after modification, there are problems such as poor compatibility between inorganic fillers and IIR and poor dispersibility of inorganic fillers in IIR. Summary of the invention

[0004] In order to make up for the deficiencies of the prior art, the present invention provides a method for preparing a high-barrier bio-based polyester PEF-filled IIR composite material, so as to at least solve or alleviate one problem in the prior art.

[0005] The technical solution adopted by the present invention to solve the above technical problems is:

[0006] A method for preparing a high-barrier bio-based polyester PEF-filled IIR composite material comprises the following steps: firstly mixing 100 parts by weight of IIR and 2.5-10 phr of PEF to obtain a uniformly mixed rubber; then adding zinc oxide, stearic acid, accelerator TMTD, accelerator M and sulfur to vulcanize the rubber mixture to obtain a composite material PEF / IIR.

[0007] Preferably, during the vulcanization treatment, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of accelerator TMTD, 0.5 parts by weight of accelerator M, and 1.5 parts by weight of sulfur are added.

[0008] Preferably, during the vulcanization treatment, the vulcanization temperature is 170° C., the vulcanization pressure is 15 MPa, and the vulcanization time is no more than 9.38 min.

[0009] Preferably, 5 phr of PEF is mixed with 100 phr of IIR. The air permeability coefficient of the obtained composite material PEF / IIR can reach 3.04×10 -11 cm 3cm / (cm 2 s·Pa).

[0010] Preferably, the preparation method of the PEF used is as follows: PEF is prepared by an esterification-polycondensation method, using FDCA and EG with a molar ratio of 1:1.8 as raw materials, DBTO as a catalyst, esterification at 200°C for 4h under a nitrogen atmosphere, and then vacuum polycondensation at 230°C for 4h to obtain PEF.

[0011] The obtained composite material PEF / IIR has a tensile strength of not less than 7.42 MPa, an elongation at break of not less than 506.8%, and a tear strength of not less than 12.28 N·mm.

[0012] The present invention adopts the above structure, and has the advantages of:

[0013] 1. Using PEF to reinforce IIR can promote the vulcanization of IIR.

[0014] 2. The method for preparing the composite material PEF / IIR is relatively simple and easy to promote and apply.

[0015] 3. In the prepared composite material PEF / IIR, the amount of reinforcing agent PEF is small and has good compatibility with IIR. When PEF is mixed with IIR in a certain proportion, PEF can be very well dispersed in IIR, that is, it has better dispersibility.

[0016] 4. Compared with IIR, the prepared composite material PEF / IIR has effectively improved mechanical properties such as tensile strength, elongation at break and tear strength. 5PEF has the best mechanical properties, with its tensile strength, elongation at break and tear strength increased by 168%, 49% and 39% respectively compared with IIR.

[0017] 5. The gas barrier property of the prepared composite material PEF / IIR is significantly improved compared with IIR. The air permeability coefficient of 5PEF reaches 3.04×10 -11 cm 3 cm / (cm 2 s·Pa); the air permeability coefficient of 10PEF reaches 2.39×10 -11 cm 3 cm / (cm 2 s·Pa). BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1HNMR spectrum of the PEF synthesized by the present invention;

[0019] Figure 2 FT-IR spectra of IIR, PEF and 5PEF;

[0020] Figure 3 is the vulcanization curve of PEF / IIR composites with different PEF contents;

[0021] Figure 4 is the SEM image of PEF / IIR composites with different PEF contents;

[0022] Figure 5 The gas barrier properties of IIR, 5PEF and 10PEF. DETAILED DESCRIPTION

[0023] In order to clearly illustrate the technical features of the present solution, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0024] 1. Instruments and reagents

[0025] 1.1 Instrument

[0026] Mixing mill: 89-8175-AL, Baopin Precision Instrument Co., Ltd.; Flatbed vulcanizer: TY-6002, Taiwan High Speed ​​Rail Testing Instrument Co., Ltd.; Infrared spectrometer: Tensor27, BRUKER, Germany; Universal testing machine: TCS-2000, Taiwan High Speed ​​Rail Testing Instrument Co., Ltd.; Scanning electron microscope: ZEISS Gemini 300, Carl Zeiss (Shanghai) Management Co., Ltd.; Gas permeameter: VAC-V2, Jinan Languang Electromechanical Equipment Co., Ltd.

[0027] 1.2 Reagents

[0028] Butyl rubber (IIR): brand 1751, China Petrochemical Corporation; furandicarboxylic acid (FDCA): 98%, Shanghai MacLean Biochemical Technology Co., Ltd.; ethylene glycol (EG): 99%, Guangdong Guanghua Technology Co., Ltd.; dibutyltin oxide (DBTO): 98%, Acros Organics; deuterated trifluoroacetic acid (TFA-D): analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.; other compounding agents are commercially available.

[0029] Preparation method of 2PEF / IIR composite material

[0030] 2.1 Preparation of PEF

[0031] PEF was prepared by esterification-polycondensation method, using FDCA and EG (molar ratio of 1:1.8) as raw materials, DBTO as catalyst, esterification at 200 ° C for 4 h under nitrogen atmosphere, and then vacuum polycondensation at 230 ° C for 4 h to obtain the product. The reaction formula is as follows:

[0032]

[0033] 2.2 Preparation of PEF / IIR composites

[0034] 100 parts by weight of IIR and prepared PEF (content of 2.5-10 phr) were mixed on a two-roll mill, and 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of accelerator TMTD, 0.5 parts by weight of accelerator M and 1.5 parts by weight of sulfur were weighed and added according to the basic formula. The mixed rubber was vulcanized on a flat vulcanizer at a vulcanization temperature of 170°C, a pressure of 15 MPa, and a time of positive vulcanization time (T90).

[0035] In the above preparation, the composite materials PEF / IIR were prepared respectively with the amount of PEF added as a variable, and the composite materials PEF / IIR corresponding to the PEF addition amounts of 2.5phr, 5phr, 7.5phr and 10phr were marked as 2.5PEF sample, 5PEF sample, 7.5PEF sample and 10PEF sample respectively, the sample without PEF was set as the blank control group IIR sample, and the PEF prepared in 2.1 was used as the control group PEF sample.

[0036] 3. Sample testing and characterization

[0037] 3.1 NMR analysis of PEF

[0038] The synthetic product prepared in 2.1 was characterized by nuclear magnetic resonance spectroscopy (1HNMR), and deuterated trifluoroacetic acid (TFA-D) was used as solvent to obtain the corresponding 1HNMR spectrum. Figure 1 .

[0039] pass Figure 1 It can be seen that the area ratio of the two peaks with chemical shifts of 7.26ppm (a) and 4.68ppm (b) is 1:2, which correspond to the hydrogen atoms on the furan ring and the methylene hydrogen atoms in ethylene glycol, respectively, indicating that PEF was successfully prepared.

[0040] According to GB / T 14190-2008, the intrinsic viscosity of PEF was tested using an Ubbelohde viscometer, and the intrinsic viscosity of the product PEF was 0.48 dL / g.

[0041] 3.2 FT-IR analysis of samples IIR, PEF and 5PEF

[0042] Fourier transform infrared spectrometer was used to characterize the infrared spectra of IIR sample, PEF sample and 5PEF sample respectively, and the test wave number range was 4000-500cm -1 , and obtain the corresponding FT-IR spectrum, see Figure 2 .

[0043] pass Figure 2 It can be seen that in the IIR curve, 2950cm-1 The strong absorption peak at 1230cm is the stretching vibration of -CH3. -1 The peak at 1370cm is the vibration of the molecular skeleton. -1 The peak is the symmetric deformation vibration of -CH3, 1467cm -1 The peak corresponds to the in-plane bending vibration of -CH2-, 1600cm -1 The peak corresponds to the symmetric stretching vibration of the C=C of the isoprene segment. In the PEF curve, 3121cm -1 and 1578cm -1 The peaks at 1014 cm-1 correspond to the stretching vibration peaks of the furan ring =CH and -C=C-, respectively. -1 and 951cm -1 The stretching vibration of furan ring COC is 817 cm -1 and 755cm -1 The bending vibration peak of the furan ring is 2962 cm -1 is the stretching vibration peak of -CH2-, 1708cm -1 The stretching vibration peak of -C=O is 1258cm -1 、1214cm -1 、1104cm -1 The vibration peaks of PEF structural units all appear, and at 3590cm -1 The stretching vibration peak of -OH of the synthesized monomer almost disappears, further proving that PEF is successfully prepared. The 5PEF curve is similar to IIR, which is due to the low content of PEF and its characteristic peak is not obvious.

[0044] 3.3 Analysis of vulcanization performance of PEF / IIR rubber compounds

[0045] The curing characteristics data and curing curves of PEF / IIR compound rubber are shown in Tables 1 and Figure 3 .

[0046] Table 1 Vulcanization data of PEF / IIR compounds

[0047]

[0048] Note: MH-maximum torque, ML-minimum torque, t90-positive vulcanization time.

[0049] From Table 1 and Figure 3 It can be seen that the addition of PEF increases the ML value of the rubber mix, but the change is not obvious with the increase of PEF content. The MH-ML value shows an upward trend, indicating that the addition of PEF reduces the fluidity of the rubber mix and increases the crosslinking density. The positive vulcanization time t90 of IIR is shortened, indicating that the addition of PEF promotes the vulcanization of the rubber mix.

[0050] 3.4 Scanning electron microscopy analysis of PEF / IIR composites

[0051] The dispersion of PEF in the matrix was analyzed by scanning electron microscopy (accelerating voltage 20 kV, and the sample was gold-sprayed before testing). The obtained SEM photos are shown in Figure 4 , where a, b, c and d correspond to samples IIR, 2.5PEF, 5PEF and 10PEF, respectively.

[0052] Depend on Figure 4 It can be seen that in the SEM images of samples 2.5PEF and 5PEF, PEF is relatively evenly dispersed in the matrix with a size of 2-4μm. Compared with other samples, slightly larger pieces of PEF appear in the SEM image of 10PEF, which indicates that the dispersion is better when the PEF content is less than 5 parts. When the content is too high, a certain degree of agglomeration will occur, which will reduce the dispersion.

[0053] 3.5 Mechanical properties analysis of PEF / IIR composites

[0054] The tensile properties of the composite material PEF / IIR were tested according to ASTM D 412-87, with a tensile rate of 500 mm / min. The tear strength of the composite material PEF / IIR was tested according to ASTM D 624-81, and the test results are shown in Table 2.

[0055] As shown in Table 2, with the addition of PEF, the tensile strength, elongation at break and tear strength of the composite material PEF / IIR are effectively improved, showing a trend of first increasing and then decreasing. The tensile strength, elongation at break and tear strength of 5PEF are increased by 168%, 49% and 39% respectively compared with IIR. Combined with the SEM photos, it can be seen that when the PEF content is low, the PEF dispersed phase is evenly distributed, acting as a physical cross-linking point, improving the mechanical properties of the material; when the PEF content is too high, the PEF dispersion decreases, local agglomeration occurs, resulting in reduced mechanical properties.

[0056] Table 2 Mechanical properties of PEF / IIR composites

[0057]

[0058] 3.6 Analysis of gas barrier properties of PEF / IIR composite materials

[0059] The barrier properties of the composite material PEF / IIR were tested by a differential pressure gas permeometer, the gas was N2, the sample thickness was 1mm, and the test temperature was 40°C. The gas barrier properties of the composite material PEF / IIR are shown in Figure 5 .

[0060] Depend on Figure 5 It can be seen that the IIR air permeability coefficient is 9.44×10 -11 cm 3 cm / (cm 2 s·Pa), and the gas barrier performance is good. However, the air permeability coefficient of the composite material PEF / IIR decreases significantly with the increase of PEF content. The air permeability coefficients of 5PEF and 10PEF are 3.04×10 -11 cm 3 cm / (cm 2 s·Pa) and 2.39×10 -11 cm 3 cm / (cm 2 s·Pa), which are 68% and 75% lower than those of IIR, respectively, indicating that PEF can further improve the gas barrier performance of IIR. This is because the nonlinear structure and polarity of PEF make it difficult for the furan ring in polyester to flip, inhibiting the permeation and diffusion of gas.

[0061] In summary, the use of PEF to reinforce IIR can improve the defects of IIR reinforced with inorganic materials, such as poor compatibility and poor dispersibility, and the resulting composite material PEF / IIR has good mechanical properties and gas barrier properties. In the actual application of composite materials, the corresponding composite materials can be prepared by focusing on selecting better performance data according to the actual needs of the field.

[0062] The above specific implementations cannot be used as limitations on the scope of protection of the present invention. For those skilled in the art, any replacement, improvement or change made to the implementations of the present invention falls within the scope of protection of the present invention. The parts not described in detail in the present invention are all known technologies to those skilled in the art.

Claims

1. A method for preparing a high barrier bio-based polyester PEF filled IIR composite material, characterized in that: The method comprises the following steps: firstly mixing 100 parts by weight of IIR and 2.5-10 phr of PEF to obtain a uniformly mixed rubber; then adding zinc oxide, stearic acid, accelerator TMTD, accelerator M and sulfur to vulcanize the mixed rubber to obtain a composite material PEF / IIR.

2. The method for preparing a high barrier bio-based polyester PEF filled IIR composite material according to claim 1, characterized in that: During the vulcanization treatment, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of accelerator TMTD, 0.5 parts by weight of accelerator M, and 1.5 parts by weight of sulfur were added.

3. The method for preparing a high barrier bio-based polyester PEF filled IIR composite material according to claim 1 or 2, characterized in that: During the vulcanization treatment, the vulcanization temperature is 170°C, the vulcanization pressure is 15MPa, and the vulcanization time is not higher than 9.38min.

4. The method for preparing a high barrier bio-based polyester PEF filled IIR composite material according to claim 1, characterized in that: 5 phr of PEF was mixed with 100 phr of IIR.

5. The method for preparing a high barrier bio-based polyester PEF filled IIR composite material according to claim 1, characterized in that: The preparation method of the PEF used is as follows: PEF is prepared by an esterification-polycondensation method, using FDCA and EG with a molar ratio of 1:1.8 as raw materials and DBTO as a catalyst, esterifying at 200°C for 4h under a nitrogen atmosphere, and then vacuum polycondensing at 230°C for 4h to obtain PEF.

6. The method for preparing a high barrier bio-based polyester PEF filled IIR composite material according to claim 1, characterized in that: The tensile strength of the composite material PEF / IIR is not less than 7.42MPa, the elongation at break is not less than 506.8%, and the tear strength is not less than 12.28N·mm.

Images