Background technology
Polyester has a large amount of carboxyls and hydroxyl conventionally in its surface, easily under the environment that contains moisture, is hydrolyzed, and often produces deterioration.Therefore, wait without under the environment being often exposed among wind and rain, the hydrolysis of the polyester that solar modules is used need to be inhibited.
In order to make polyester produce hydrolytic resistance, there is people to carry out catalytic hydrolysis reaction to it and reduce terminal hydroxyl, in order effectively to reduce terminal hydroxyl, tend to use some effective end closure agent as additive.
But the vibrin that is added with end closure agent has a lot of drawbacks in melt extruding, when melting mixing, end closure agent meeting produces the foreign matter such as gel, and the volatile component that part has neither part nor lot in reaction causes engineering to pollute, and operating environment is worsened.And the price of end closure agent is relatively high, a large amount of use has obstacle aborning.
Also incomplete in order to bring into play to greatest extent the effect of end closure agent, melt extrude the end closure agent reaction of adding in technique, thus after melt molding, unreacted encapsulant can continue to cause that capping effectively suppresses the increase of carboxyl.But just must excessive interpolation encapsulant in order to obtain this kind of effect.
And, in order to obtain the good polyester film of weather resistance, reduce terminal hydroxyl quantity, namely use the resin raw material that AV value is lower to obtain solid state polymerization particle.But when solid state polymerization particle uses, the very large shear heat of needs when improving limiting viscosity melting promotes the decomposition reaction of encapsulant.
But, when melting, often adopt low temperature to extrude in order to suppress resin decomposition, but cannot fully carry out capping under low temperature, simultaneously, in the resin raw material of low temperature, the degree of crystallization of the nuclei of crystallization of molten component on film is not higher, and overtension when extension is difficult to launch completely.
Summary of the invention
The object of the present invention is to provide the method for the polyester film that output anti-hydrolytic performance is good in the component volatilization amount in a kind of usage quantity and technique reducing end closure agent.
The present invention is achieved by the following technical solutions:
The manufacture method of described polyester resin film, limiting viscosity is mixed in vibrin and the end closure agent of 0.6~0.65dl/g, end closure agent institute accounting is for being 0.6~1.2%, the two is adopted to forcing machine melting mixing, when the fusing point of described polyester film is T, the temperature in described forcing machine region is T ℃~T+200 ℃, carries out with this understanding the expressing technique of molten resin.
Further, described vibrin is unsaturated polyester resin.
Further, described vibrin is that TriMethylolPropane(TMP) and m-phthalic acid are synthetic, and has carried out viscosity modification with thinner.
Further, described end closure agent is carbodiimide.
Further, add the moisture control of vibrin of described forcing machine between 10~100ppm.
Further, described forcing machine is biaxial extruder, and the pressure-controlling of extrusion is between 800~1000Pa.
Further, the temperature in described forcing machine region is T ℃~T+150 ℃.
Beneficial effect of the present invention is to describe in conjunction with relevant data in embodiment part.
Embodiment
Below in conjunction with embodiment, the present invention is further elaborated:
Limiting viscosity is mixed in vibrin and the end closure agent of 0.6~0.65dl/g, end closure agent institute accounting is for being 0.6~1.2%, the two is adopted to forcing machine melting mixing, when the fusing point of described polyester film is T, the temperature in described forcing machine region is T ℃~T+200 ℃, carries out with this understanding the expressing technique of molten resin.
Above-mentioned raw material also can be encapsulated as half-finished Preblend after making, and reuses when needed.
Described vibrin is unsaturated polyester resin.When unsaturated polyester is synthetic, range of viscosities is more easily controlled.
Described vibrin is that TriMethylolPropane(TMP) and m-phthalic acid are synthetic, and has carried out viscosity modification with thinner.Thinner can be selected organic alcohols, and as ethanol, or the inorganic powder of inertia also can.
Described end closure agent is carbodiimide.
Add the moisture control of vibrin of described forcing machine between 10~100ppm.When excess moisture, easily produce vapour pressure, be unfavorable for that product is synthetic.
Described ratio equivalent is 10~15eq/t.End closure agent price is high, under the prerequisite that does not have obviously to reduce, reduces and uses as far as possible in effect.
Described forcing machine is biaxial extruder, and the pressure-controlling of extrusion is between 800~1000Pa.This can be adjusted according to actual needs, sees the resin kind of selecting.
The temperature in described forcing machine region is T ℃~T+150 ℃.
The preferred extrusion way of the present invention is, biaxial extruder screw diameter is L, its screw rod direction longitudinal length is 5L~10L, in this region, heat, wherein resin enters with the temperature of 170 ℃, in the process to outlet motion, be heated to the highest 300 ℃, then the edge heating temperature of outlet of extruder temperature is 70 ℃, according to this technique, because the fusing point half of resin itself is more than 100 degree, treat that curing liquid resin should not export out quenching, thereby outlet need to keep certain temperature, make the resin can quenching moulding, also can be not overheated and mobility causes excessively being by force difficult to moulding control.
Below provide processing parameter and the product performance data of the film that the present invention makes.
Brief description about upper table data is as follows:
IV value is limiting viscosity; AV value is acid number, and 7, No. 8 examples are comparative example.
The present invention is in the time selecting end closure agent concentration, needn't take the doubly mode of excessive use of 4-5 in the past, can not cause after reaction finishes, also having more than half encapsulant remnants, the reactivity of encapsulant is more than 50%, reacting weight was with level was fair in the past, thereby sealing effect does not obviously reduce, simultaneously, in the present invention, can not produce too much volatile constituent when the high temperature because of the abundant residues of encapsulant and affect product performance, the elongation at break of product own can reach that more than 100% (conventional polyester film is about 100%, after modification, can improve), can meet its application requiring.
In comparative example, change the limiting viscosity of vibrin, will produce the doubly excessive situation (No. 8 examples) that just can obtain desired product of reacting with end closure agent of 4-5 in the past, or do not use enough end closure agent just cannot obtain the situation (No. 9 examples) of qualified product, simultaneously, for this series products, the uniformity coefficient that single axle extruding machine is extruded does not have the effective of biaxial extruder.
One of purposes of the present invention is can be used as protecting solar cell cover, and rete wraps series of cells in day side, and is fixed by described clamping plate in backlight.
Another purposes of the present invention is can be used as the rete of simple and easy solar seawater desalination treating pond, comprise internal layer seawater pond and outer fresh-water pool, top is attached with transparent film layer and connects and wrap fresh-water pool, in inner seawater pond, moisture evaporates and is condensed on rete and flows into fresh-water pool, and fresh-water pool top is provided with dividing plate and prevents moisture evaporation in fresh-water pool.
The detailed description of this patent being made according to above specification sheets; its object is to be convenient to those skilled in the art better understands application mode and the scope of this patent; can not be interpreted as limitation of the present invention; in conjunction with the general knowledge of above content and this area; under the prerequisite of aim that does not depart from this patent, what those skilled in the art made the technical scheme of recording in this patent document be equal to alternative still falls into protection scope of the present invention.