Patent Application
20240409522
The present disclosure belongs to the technical field of chain extenders, and in particular to a bio-based epoxy chain extender, a preparation method and an application thereof.
Polybutylene succinate (PBS) has excellent biodegradability, melt processability and chemical resistance, as well as good thermal stability and excellent mechanical properties. With the renewability of the synthesized monomers and properties comparable to those of traditional polyolefin plastics, PBS is considered to be a class of biodegradable materials with good prospects for development in the field of packaging films and mulch films. However, there is a major problem limiting the expanded utilization of PBS in the film field, mainly the low barrier properties to oxygen and water vapor, which make PBS incapable of meeting the high barrier requirements in packaging and mulch film applications.
Currently, the problem of poor barrier properties of PBS is addressed by adding a high barrier material, polyglycolic acid (PGA), while compatibilizers/chain extenders are added to improve the compatibility of the two in order to further enhance the phase interfacial adhesion and improve the barrier properties of the material. Since polyester contains terminal carboxyl and terminal hydroxyl groups, the functional groups of chain extenders commonly used in the prior art include epoxy groups, isocyanates, oxazolines, and so on. Epoxy compounds are usually the most used for their efficient chain extension effect, among which BASF's ADR series derived from the copolymerization of styrene and acrylic acid glycidyl ester is the most frequently used. However, ADR chain extenders are unfavorable because of the presence of benzene rings in their structure, the high molecular weight (6,000-7,000 k), the petroleum-based origin of the monomer, and the difficulty of degradation.
Therefore, a technical problem that needs to be solved by the technicians in the field is to provide a chain extender with good capacity-enhancing and chain-extending effect, as well as high stability and synthesis of monomers of biobased origin.
In order to solve the above technical problems, the present disclosure provides a bio-based epoxy chain extender, a preparation method and an application thereof.
In order to achieve the above objectives, the present disclosure provides the following technical scheme.
A preparation method of a bio-based epoxy chain extender includes the following steps:
Beneficial effect: the raw material CD in the present disclosure is a multifunctional, renewable and inexpensive organic natural resource derived from cashew nut-shell liquid, an agricultural by-product of the cashew industry, and consists of a mixture of different long-chain phenols. CD contains phenolic hydroxyl groups and double bonds, and reacts with ESO to produce a new ESOn-ECD chain extender. The preparation method is simple in process, cost-effective with high yield, and is convenient for control and large-scale production, while the produced chain extender has good capacity-enhancing effect and strong stability.
Optionally, a molar ratio of the ESO to the CD in step (1) is 3-6:1; and
Optionally, a temperature of the catalytic reaction in the step (1) is 200 degrees Celsius (° C.) with a reaction duration of 30 minutes (min).
Optionally, an addition ratio of the ESOn-CD, the concentrated sulfuric acid, the glacial acetic acid and the hydrogen peroxide in step (2) is 100 grams (g):2 milliliters (mL):10 mL:20 mL.
Optionally, a mass concentration of the concentrated sulfuric acid is 98%;
Optionally, a temperature for heating in the step (2) is 65° C.; and
A bio-based epoxy chain extender prepared by the preparation method of the bio-based epoxy chain extender.
An application of the bio-based epoxy chain extender in preparation of PBS/PGA composite material.
Optionally, the PBS/PGA composite material includes a PBS/PGA injection molded product or a PBS/PGA composite film.
More optionally, a preparation method of the PBS/PGA composite material includes the following steps:
The present disclosure provides a bio-based epoxy chain extender and a preparation method thereof. The epoxy chain extender synthesized based on biomass resources in this disclosure has excellent chain extending effect on PBS/PGA composite materials and is capable of synergistically improving the barrier property of the composite film, and also enhancing the interfacial bonding force of the two phases of PBS/PGA, thus improving the mechanical properties of PBS/PGA composite film; moreover, the bio-based epoxy chain extender provided by the present disclosure has excellent compatibilization effect, which not only solves the problem of poor compatibility of the two phases of the biodegradable polyester, but also realizes total degradation, which makes it an alternative to petroleum-based chain extender. Besides, the preparation method provided by the present disclosure requires low raw material cost and has renewable source, which is in line with the requirement of green environment protection, and the process is simple and does not pollute the environment, indicating a good substitute for petroleum-based chain extender.
The accompanying drawings, which constitute a part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application, and do not constitute an improper limitation of this application. In the attached drawings:
In the following, the technical schemes in the embodiments of the present disclosure are clearly and completely described with reference to the attached drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, but not the whole embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without creative labor belong to the scope of protection of the present disclosure.
In order to make the above objectives, features and advantages of the present disclosure more obvious and easy to understand, the present disclosure will be further described in detail with the attached drawings and specific embodiments.
Some sources of raw materials used in the embodiments of the present disclosure are as follows:
The present disclosure provides a preparation method of a bio-based epoxy chain extender, including the following steps as shown in
The preparation method of the bio-based epoxy chain extender, including the following steps:
The yield of the obtained bio-based epoxy chain extender ESO3-ECD is 90% and the epoxy value is 6.62%.
The preparation method of the bio-based epoxy chain extender, including the following steps:
The yield of the obtained bio-based epoxy chain extender ESO6-ECD is 92% and the epoxy value is 4.78%.
The structural formulas of the reactants ESO and CD used in Embodiments 1-2 and the products ESOn-ECD are shown in
The preparation method of the PBS/PGA composite material includes the following steps:
The preparation method of PBS/PGA composite material is different from Embodiment 3 in that the addition amount of bio-based epoxy chain extender obtained in Embodiment 1 is 0.5%, 0.7% and 1.0% of the total mass of PBS and PGA in turn.
The preparation method of the PBS/PGA composite material includes the following steps:
The preparation method of the PBS/PGA composite material is different from Embodiment 7 in that the bio-based epoxy chain extender obtained in Embodiment 2 accounts for 0.5%, 0.7% and 1.0% of the total mass of PBS and PGA in turn.
The preparation method of PBS/PGA composite material is different from Embodiment 3 in that the bio-based epoxy chain extender obtained in Embodiment 1 is not added.
The preparation method of the PBS/PGA composite material includes the following steps:
The preparation method of the PBS/PGA composite material is different from Embodiment 7 in that the addition amount of BASF ADR4468 is 0.5%, 0.7% and 1.0% of the total mass of PBS and PGA in turn.
The preparation method of the PBS/PGA composite film includes the following steps:
The preparation method of PBS/PGA composite film is different from Embodiment 11 in that the bio-based epoxy chain extender obtained in Embodiment 2 is used.
The preparation method of PBS/PGA composite film is different from Embodiment 11 in that no chain extender is used.
The preparation method of PBS/PGA composite film is different from Embodiment 11 in that BASF ADR4468 is used instead of the bio-based epoxy chain extender obtained in Embodiment 1.
1. The products prepared in each embodiment are characterized by the following methods.
(1)
Proton nuclear magnetic resonance (1H NMR) spectroscopy is performed on a Broker Avance 400 instrument with a frequency of 400 MHz, using CDCl3 as the solvent.
The thermal stability of each bio-based epoxy chain extender is measured by thermogravimetric analysis (TGA) in STA7200 (Hitachi, Japan). Specifically, under the condition of nitrogen purging, the heating rate is 20° C./min, and the measuring temperature range is 40-500° C. The weight loss rate of each chain extender with the increase of temperature is recorded.
(2) On the electronic universal testing machine controlled by microcomputer (CMT6104, China), the mechanical properties of injection-molded splines and films are tested according to GB/T1040.1-2006, and the elongation at break (EB, %) and tensile strength (TS, MPa) of the samples are obtained. Among them, the spacing between fixtures is set to 50 mm, the stretching speed is 50 mm/min, and each group of samples is tested for 5-10 times. The average value and the error are calculated.
Using the same machine, the tear resistance of the film is tested according to the standard of GB/T106578.1-2008. During the test, the distance between fixtures is set to 50 mm, and the tearing rate is 200 mm/min. Each group of samples is tested for 5 times, and the average value is taken according to the effective value.
(3) Under the condition of JSM-6700F voltage of 10 kV, the microstructure of the sample is analyzed by scanning electron microscope (SEM). Each group of samples is soaked in liquid nitrogen for 15 min, and a thin gold layer is coated on the fracture surface to improve the conductivity of the samples.
(4) According to ASTM D3985, the O2 permeability of PBS/PGA composite film is measured by VAC-V2 differential pressure gas permeameter at 23° C. and 30% relative humidity.
According to GB/T1037, at 38° C. and 90% relative humidity, the water vapor permeability of PBS/PGA composite film is measured by C360M weight loss method with a water vapor permeameter.
2. The characterization results and analysis are as follows:
By comparing the 1HNMR spectra, it is found that after the oxidation reaction in step (2), the signal peaks of ESOn-ECD at 5.75 ppm and 5.0 ppm are obviously reduced compared with ESOn-CD, indicating that the double bond disappears and the epoxidation reaction occurs.
The mechanical properties of composite injection-molded splines obtained in Embodiments 3-10 and Comparative embodiments 1-5 are tested, and their tensile properties and impact properties are shown in Table 4, and the compatibilization effects of different chain extenders are studied correspondingly. It is observed from Table 4 that the addition of ADR or ESOn-ECD may improve the tensile strength and elongation at break of the composite material compared with the compatibilized blends, which proves that the addition of chain extender is capable of enhancing the interfacial bonding force. The epoxy group in the chain extender reacts with carboxyl and/or hydroxyl groups of PBS and PGA, thus promoting effective immobilization between phases. With the content of chain extender increasing from 0.3% to 0.7%, the tensile strength, elongation at break, tensile modulus and impact strength of the composite material are all increased. However, when the content of chain extender continues to increase to 1.0%, the mechanical properties will decrease, which is mainly caused by excessive chain extender. The excessive chain extender fails to react with the terminal carboxyl group of PBS and PGA, and it plays a plasticizing role in the composite, which will lead to the decrease of mechanical properties.
It may be further observed from Table 4 that the component with 0.7% chain extender in the composite material has the best mechanical properties, among which ESOn-ECD shows a better value than ADR, which may be due to its lower viscosity, as ESOn-ECD is an oily liquid with a molecular weight of about 1,000, while ADR is in a solid powder state with a molecular weight of about 6,000-7,000. Generally, during melt mixing, the components with lower viscosity in the blend tend to encapsulate other components. Therefore, ESOn-ECD should be easier to migrate to the phase interface between PGA and PBS, thus serving as a bridge between the two phases. In addition, the addition of ESOn-ECD also promotes the significant increase of impact strength, which further proves the enhancement of two-phase interface. From the mechanical properties, it is observed the chain extension and compatibilization effect of ESO3-ECD is better than ESO6-ECD. This is related to the number of epoxy groups, which increases as the proportion of cardanol increases in ESOn-ECD, and a higher number of epoxy groups favours a higher efficiency of the reaction and accelerates the chain extension reaction.
After adding 0.7% ADR or ESO3-ECD in Comparative embodiment 4 and Embodiment 5, the phase interface is decreased. The composite injection-molded spline obtained in Embodiment 5 shows a small and well-adhered PGA dispersed phase, in addition to improved compatibility and better interface adhesion.
The composite films obtained in Embodiments 11-12 and Comparative embodiments 6-7 are shown in
Tables 5 and 6 show the mechanical properties of PBS/PGA composite films obtained in Comparative embodiments 6-7 and Embodiments 11-12. As shown in the results, the tensile and tear properties of the composite films obtained in Embodiment 11 are the best.
In addition, as shown in Table 7, the composite film obtained in Embodiment 11 exhibits the lowest oxygen and water vapour permeability and has good barrier properties due to the reduction of the phase interfaces as compared to the unmodified composite film obtained in Comparative embodiment 6.
According to the present disclosure, a bio-based epoxidized compound is prepared from biological cardanol and epoxidized soybean oil as raw materials, and is used as an active compatibilizer/chain extender additive of a PBS/PGA (80:20 wt %) blend, and meanwhile, the effectiveness of the bio-based compound is compared with the petroleum-derived glycidyl ester-based copolymer ADR4468 widely used in the prior art. The results show that compared with unmodified PBS/PGA incompatible blends, adding 0.7 part of ESO3-ECD may effectively improve the mechanical properties of composite material/films. It may be clearly seen from SEM that the addition of ESO3-ECD is capable of strengthening the phase interface of the two phases and plays a bridging role. To sum up, ESO3-ECD has excellent effect on toughening chain-extended PBS/PGA blends.
The chain extender prepared by the present disclosure is obtained from monomers of biomass origin, which is green and non-toxic, and is also a good substitute for petroleum-based chain extender. It may be directly applied in the field of food packaging, and the bio-based chain extender solves the problem of poor barrier properties of biodegradable films, as well as makes a positive significance for broadening the application field of PBS.
The above describes only the preferred embodiments of this application, but the protection scope of this application is not limited to this. Any change or replacement that may be easily thought of by a person familiar with this technical field within the technical scope disclosed in this application should be included in the protection scope of this application. Therefore, the protection scope of this application should be based on the protection scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202310666308.9 | Jun 2023 | CN | national |
This application is a continuation of PCT/CN2024/073543, filed Jan. 23, 2024 and claims priority of Chinese Patent Application No. 202310666308.9, filed on Jun. 7, 2023, the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2024/073543 | Jan 2024 | WO |
| Child | 18764298 | US |
