Disclosure of Invention
The invention aims to solve the technical problems that graphene is easy to break and fall off from the surface of a base material when an external force is applied to a diaphragm in the prior art, and the high-frequency and low-frequency performance is not good enough.
The technical scheme adopted by the invention for solving the technical problems is as follows: constructing a diaphragm comprising:
the base layer is a film made of any one of materials of polyetherimide, polyethylene terephthalate, polyether ether ketone, polyphenylene sulfide and polyurethane;
the strengthening layer is a mixture formed by mixing graphene, graphite powder and glue and is formed by drying and curing, wherein,
the weight ratio of the graphite powder to the graphene to the glue in the strengthening layer is (1-2) to (5-10) to (9994-9988);
the strengthening layer is adhered to the surface of the base layer.
In the diaphragm, the thickness of the diaphragm reinforcing layer is preferably 2 μm.
A preparation method of the diaphragm comprises the following steps:
s1: providing a film, glue, graphite powder and graphene;
s2: uniformly mixing the graphite powder and the graphene to form a first mixture, adding the first mixture into the glue water, mixing and uniformly stirring to form a second mixture;
s3: and uniformly coating the second mixture on the surface of the film, and drying to solidify the second mixture on the surface of the film to obtain the final diaphragm.
In the preparation method of the diaphragm, preferably, before the step S3, the surface of the film is pretreated, where the pretreatment is to clean the surface of the film.
In the preparation method of the diaphragm, the weight ratio of the graphite powder, the graphene and the glue in the second mixture is preferably (1-2): (5-10): 9994-9988.
In the preparation method of the diaphragm, the thickness of the second mixture coated on the film is preferably 2 μm.
In the preparation method of the diaphragm, the film is preferably made of any one of polyetherimide, polyethylene terephthalate, polyether ether ketone, polyphenylene sulfide and polyurethane.
In the preparation method of the diaphragm, the glue is preferably any one of polyurethane, vinyl fluoride, polyacrylate emulsion, vinyl acetate and ethylene-vinyl acetate.
In the preparation method of the diaphragm, preferably, in step S2, the second mixture is uniformly coated on the surface of the film in a slit coating manner.
In the preparation method of the diaphragm, preferably, in the step S2, the second mixture is uniformly coated on the surface of the film by a mesh coating method.
The diaphragm of the invention has the following beneficial effects: the vibrating diaphragm comprises a base layer and a strengthening layer, wherein the strengthening layer is coated on the surface of the base layer, the base layer is a thin film made of any one of materials including polyetherimide, polyethylene glycol terephthalate, polyether ether ketone, polyphenylene sulfide and polyurethane, the strengthening layer is a strengthening layer formed by mixing and drying and curing graphene, graphite powder and glue, and the weight ratio of the graphite powder to the graphene to the glue in the strengthening layer is (1-2) to (5-10) to (9994-9988). The graphite powder, graphite alkene and glue after intensive mixing of adoption scribble the basal layer surface again, can make graphite alkene homogeneous cure in the colloid, can be with the help of the adhesive force adhesion of colloid at the basal layer surface, the adhesion of graphite alkene makes graphite alkene be difficult for the fracture, is difficult to drop from the basal layer surface to when having realized improving vibrating diaphragm high frequency characteristic and can having taken into account its low frequency performance, still can effectively improve adhesion, the reliability of graphite alkene, the stability of improvement vibrating diaphragm.
Detailed Description
For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
As shown in fig. 1, the present invention provides a diaphragm, which includes a base layer 101, and a reinforcing layer 102 attached to a surface of the base layer 101. The base layer 101 is a film made of any one of polyetherimide, polyethylene terephthalate, polyether ether ketone, polyphenylene sulfide, and polyurethane. Preferably, the base layer 101 is a film made of polyethylene terephthalate, i.e. preferably a PET (polyethylene terephthalate) film, as a base material of the diaphragm.
The strengthening layer 102 is formed by drying and curing a mixture formed by uniformly mixing graphene, graphite powder and glue.
In the strengthening layer 102, glue is used for dispersing graphene; in the invention, the glue is applicable to any glue for dispersing graphene, and is not limited, and the glue can be any one of polyurethane, vinyl fluoride, polyacrylate emulsion, vinyl acetate and ethylene-vinyl acetate. Polyurethane is preferred.
In the invention, the graphite powder, the graphene and the glue can be mixed according to different proportions, and the weight ratio of the graphite powder to the graphene to the glue is preferably (1-2) to (5-10) to (9994-9988).
It can be understood that, in the present invention, the graphite powder is added to the strengthened layer 102, because the graphite powder has a relatively good heat dissipation performance, and the diaphragm can generate a high amount of heat during vibration, the addition of the graphite powder can help the diaphragm to dissipate heat, and when the diaphragm is applied to an acoustic device such as a speaker, the bearing capacity of the speaker can be improved. The graphene has the characteristic of single atom rigidity, so that the graphene has strong rigidity and good overall performance, and the characteristic of the vibrating diaphragm can be changed by adding the graphene into the strengthening layer 102, so that the vibrating diaphragm can achieve the high-frequency performance of metal plating, and simultaneously can achieve better low-frequency performance, thereby improving the overall effect of the vibrating diaphragm. Preferably, the thickness of the strengthening layer 102 is 1.5 to 3.5 μm, more preferably 2 μm.
In addition, the vibrating diaphragm provided by the invention has the advantages of good rigidity, high adhesion and better high-low frequency performance, and can be suitable for acoustic equipment such as a loudspeaker, a receiver and the like.
The invention provides a preparation method of a vibrating diaphragm, which comprises the following steps:
s1: a film, glue, graphite powder and graphene are provided.
In step S1, the film is made of any one of polyetherimide, polyethylene terephthalate, polyetheretherketone, polyphenylene sulfide, and polyurethane. Polyethylene terephthalate (PET) is preferred.
The glue is any one of polyurethane, vinyl fluoride, polyacrylate emulsion, vinyl acetate and ethylene-vinyl acetate, and preferably polyurethane.
S2: the preparation method comprises the steps of uniformly mixing graphite powder and graphene to form a first mixture, adding the first mixture into glue water, mixing and uniformly stirring to form a second mixture. It can be understood that the graphite powder, the graphene and the glue can be mixed according to different proportions, and the proportion that the graphite powder and the graphene can be completely dispersed in the glue is suitable for the invention, but the invention is not limited to this, and the weight ratio of the graphite powder, the graphene and the glue is preferably (1-2): (5-10): 9994-9988).
S3: and uniformly coating the second mixture on the surface of the film, and drying to solidify the second mixture on the surface of the film to obtain the final diaphragm. Preferably, before step S3, the surface of the film is pretreated, that is, before the second mixture is uniformly coated on the surface of the film, the surface of the film needs to be cleaned, for example, to remove impurities such as dust on the surface of the film, so as to enhance the adhesion of the surface of the film. Further, the thickness of the second mixture coated on the surface of the film is 1.5-3.5 μm, and preferably 2 μm.
The second mixture is coated on the surface of the film by a slit coating method or a cross-hatch coating method, and the specific coating parameters can be determined according to the actual coating conditions, which is not limited in the present invention.
In the embodiment of the invention, the second mixture formed by uniformly mixing the graphite powder, the graphene and the glue is uniformly coated on the surface of the film in a slit coating or reticulate coating mode, so that the graphene and the graphite powder are more firmly adhered to the surface of the film by virtue of the adhesive force of the glue. Because graphite powder, graphite alkene even solidification are in glue and the adhesion is on the film surface to make the vibrating diaphragm that forms have better homogeneity, uniformity, be difficult for producing and split the vibration, the vibrating diaphragm intensity that adopts this preparation method to make simultaneously is high, and the rigidity is strong, and high and low frequency performance is better, has effectively improved the acoustic effect of vibrating diaphragm.
The preparation of graphite powder, graphene and glue mixed is illustrated by the following examples:
example 1
A. Graphite powder, graphene and glue are mixed, 1g of graphite powder, 5g of graphene and 9994g of glue are taken, 1g of graphite powder and 5g of graphene are uniformly mixed respectively, and the powder obtained by mixing the graphite powder and the graphene is doped into the 9994g of glue and stirred, so that the graphite powder and the graphene are uniformly distributed in the glue.
B. After the graphite powder and the graphene are uniformly distributed on the glue, coating a mixture formed by the graphite powder, the graphene and the glue on the surface of the film, and drying the film coated with the mixture of the graphite powder, the graphene and the glue to enable the colloid to be solidified and adhered on the surface of the film.
Example 2
A. Graphite powder, graphene and glue are mixed, 1.5g of graphite powder, 7.5g of graphene and 9991g of glue are taken, 1.5g of graphite powder and 7.5g of graphene are respectively and uniformly mixed, and the mixed powder of the graphite powder and the graphene is doped into 9991g of glue and stirred, so that the graphite powder and the graphene are uniformly distributed in the glue.
B. After the graphite powder and the graphene are uniformly distributed on the glue, coating a mixture formed by the graphite powder, the graphene and the glue on the surface of the film, and drying the film coated with the mixture of the graphite powder, the graphene and the glue to enable the colloid to be solidified and adhered on the surface of the film.
Example 3
A. Graphite powder, graphene and glue are mixed, 2g of graphite powder, 10g of graphene and 9988g of glue are taken, 2g of graphite powder and 10g of graphene are uniformly mixed respectively, and the powder obtained by mixing the graphite powder and the graphene is doped into 9988g of glue and stirred, so that the graphite powder and the graphene are uniformly distributed in the glue.
B. After the graphite powder and the graphene are uniformly distributed on the glue, coating a mixture formed by the graphite powder, the graphene and the glue on the surface of the film, and drying the film coated with the mixture of the graphite powder, the graphene and the glue to enable the colloid to be solidified and adhered on the surface of the film.
The following performance tests were performed by comparing the conventional loudspeaker assembled with a diaphragm with the loudspeaker assembled with a diaphragm of the present invention:
high-low frequency performance test of vibrating diaphragm
The frequency response of the diaphragm manufactured in embodiments 1 to 3 in the vibration process is evaluated to reflect the high and low frequency performance of the diaphragm. The evaluation method comprises the following steps: the prepared diaphragm is formed into a loudspeaker diaphragm, and a finished product (called as a graphite powder-graphene loudspeaker, and the same is used hereinafter) is assembled, and the acoustic performance test is carried out on the diaphragm and a common loudspeaker, wherein the specific test method is that a standard acoustic performance tester is adopted to simultaneously test the graphite powder-graphene loudspeaker and the common loudspeaker, the test time is 10 minutes, corresponding data recording is carried out, and the frequency response curve is shown in fig. 2.
According to the recorded data and the frequency response curve chart (fig. 2), the high-frequency response curve of the graphene loudspeaker is 2-4 dB higher than that of a common loudspeaker (the high frequency range is 3000-40000 Hz), and the low-frequency response curve of the graphene loudspeaker is 3-6 dB higher than that of the common loudspeaker (the low frequency range is 20-50 Hz).
As shown in fig. 3, which is a graph of impedance curve of a loudspeaker assembled by a diaphragm of the present invention and a common diaphragm, it can be directly seen from the graph: low-frequency resonant frequency f of graphite powder-graphene horn0Is about 150Hz lower than that of the common horn.
The experimental results directly illustrate that the vibrating diaphragm has better high-low frequency performance and strong rigidity, and the graphite powder and the graphene are directly and uniformly mixed into the glue, so that the vibrating diaphragm has higher adhesion and is not easy to fall off.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.
It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.