CN105128277A - Mold internal self-enhancement co-injection molding method of monopolymer composite material - Google Patents

Abstract

The invention discloses a mold internal self-enhancement co-injection molding method of a monopolymer composite material, and belongs to the injection molding mold technical field. A matrix of the monopolymer composite material is molded through an injection molding method firstly, the surface of the matrix is provided with reserved grooves, the matrix is put into the mold again, the grooves on the matrix are filled to obtain the monopolymer composite material, and thus injection molding of all components of the monopolymer composite material is completed by using one set of mold; the problems that complex process, long molding period and strict requirements of raw materials in preparation of the monopolymer composite material by ways of hot pressing, extrusion and injection molding are overcome. The method for mold internal self-enhancement co-injection molding of the monopolymer composite material can realize mass production and can be applied to actual production of monopolymer composite material products.

Description

Self-reinforcing injection molding forming method altogether in a kind of single polymer composites mould

Technical field

The invention belongs to injecting molding die technical field, single polymer composites (SinglePolymerComposites is prepared in the self-strengthening method and the injection moulding that relate to polymer, SPC) method, is specifically related to self-reinforcing injection molding forming method altogether in a kind of single polymer composites mould.

Background technology

Polymer has that processing technology is good, density is little, specific strength high (specific strength of polymer, far above cement concrete, close to even having exceeded steel, belongs to a kind of material of high-strength light), good chemical stability.Along with developing rapidly of human being's production force level, the range of application of polymer is more and more wider, and the polymeric material of one-component has been difficult to meet growing instructions for use, and in this case, polymer composites arises at the historic moment.According to the difference of wild phase, polymer composites can be divided into fiber reinforcement type, Whisker reinforced and granule enhancement type, relative to conventional metals composite, polymer composites has the advantages such as density is little, the scope of application is wide.But the wild phase of general composite and matrix adopt different materials, different materials contacts with each other with regard to Presence of an interface consistency problem, and the overall performance impact of interface performance on composite is very large; Further, along with the minimizing gradually of earth resource, environmental problem becomes increasingly conspicuous, and traditional polymer composite is difficult to matrix to be effectively separated with reinforcing material, thus brings great difficulty to recycling.

Single polymer composites (SPC) is a kind of novel polymer composites, and its matrix and wild phase are similar polymers, therefore, there is not material interface poor compatibility and reclaims the problem of difficulty; For similar polymers, the mechanical property of SPC is far superior to the shaping material of single, and without the need to wild phase is got final product direct recycling with being separated of matrix.Therefore, SPC has huge researching value and application prospect.But the reinforcement of SPC and matrix are commaterial, and its fusing point is identical, cause the technics comparing preparing SPC complicated, preparation technology becomes the bottleneck of the single polymer composites development of restriction.The main method of current preparation list polymer composites has: hot pressing method, extrude preparation method and injection moulding preparation method.

The first method of hot pressing SPC is melt impregnation, this method proposes the earliest, and prepare SPC sample, the fibers parallel prepared by polymeric material is layered between two-layer similar polymers sheet material, then, the material of sandwich structure is placed on hot press, is heated to predetermined temperature and applies pressure, keep certain hour, obtain SPC; The another kind of method of hot pressing SPC is solution dipping method, by wild phase fiber impregnation in the organic solvent being dissolved with this kind of polymer, polymer is separated out and is sticked on polymer fiber from solution, the fiber utilization hot pressing mode obtained is prepared SPC, and the polymer meeting melting recrystallization of fiber surface forms the matrix of SPC.Compared with melt impregnation, solution dipping method does not require that the melt viscosity of matrix is low, and distribution of polymer between fiber is more even, and the mechanical property of the SPC finally obtained is better, but need in the method to use a large amount of organic solvents, and more consuming time; The uniform texture of SPC product prepared by hot-press method, mechanical property is given prominence to; But this method shaping efficiency is low, and preparation process is more loaded down with trivial details, strict especially to temperature controlled requirement, and pressure in forming process and heat easily affect the degree of orientation and the crystal property of fiber, thus make single polymer composites overall performance impaired.

Extrusion molding is prepared SPC and is utilized extruder that matrix material is heated to molten condition, and the matrix of molten condition is fed forward and cools the molten condition that is as the criterion under extrusion pressure effect; Then, joined by reinforcing material in the matrix of accurate molten condition, mix and be fed forward, extrusion molding obtains SPC goods.It is short that this method has molding cycle relative to the method for hot pressing, easy control of temperature, can continuous batch produce advantage, but, the method makes thermoplastic polymer fortifying fibre directly contact with the matrix polymer of molten state, the structure property of easy infringement fiber, reduces the overall performance of composite.

Injection molding prepares SPC, and the method first precasts reinforcement, and then reinforcement put into the die cavity of injection mold and fix, the matrix material that will plastify after matched moulds injects die cavity, and pressurize cooling obtains SPC.The method is relative to traditional hot-press method, there is device structure simple, the advantage of processing ease, but, the method needs to lay prefabricated reinforcement fiber in advance equally, and similar with extrusion molding, thermoplastic polymer fortifying fibre directly contacts with the matrix polymer of molten state, and the overall performance of composite can be caused to be destroyed.

Summary of the invention

There is complex manufacturing, product geometry for the existing forming method of SPC single and be difficult to realize the present situation of mass production, the present invention proposes self-reinforcing injection molding process and corresponding mould structure altogether in a kind of SPC mould.The method has that Material selec-tion is extensive, technique is simple, with short production cycle, can the advantages such as mass production be realized.Mould in the present invention, can, on common singe screw injection machine, utilize one set of die to complete the preparation of SPC.

Technical scheme of the present invention is as follows:

Self-reinforcing injection molding process altogether in a kind of single polymer composites mould, with shaping wild phase first in traditional SPC forming method, the mode of aftershaping matrix is different, and the matrix of the first injection mo(u)lding SPC of the method, then inserts shaping wild phase in another die cavity of mould by matrix.Matrix and wild phase are shaping at twice, and the shaping performance on wild phase of matrix does not affect.The performance of polymer is not only relevant, also relevant with molding mode and condition of molding with material, optimizes the molding parameter of wild phase, can obtain the SPC of best performance.

The common injection molding forming method of self-reinforcing in a kind of single polymer composites mould, in single polymer composites mould of the method, the common injection molding apparatus of self-reinforcing comprises top clamping plate, solid plate, moving platen, occurring matrix type cavity insert, wild phase cavity block and Bottom clamp plate; Moving platen has two independently grooves, be respectively used to install wild phase cavity block and occurring matrix type cavity insert, two inserts, by straight pin and side location, use bolt to be arranged on moving platen; Occurring matrix type cavity insert has along filling melt direction, has three projections of constant cross-section, for the preparation of the SPC matrix with groove structure; The die cavity of wild phase cavity block is rectangular structure, and size is identical with the contour dimension of SPC matrix, for the filling of SPC wild phase in body trench; Shaping step is as follows:

1) set the molding parameter of injection machine, be expelled in mold cavity by the polymer plastified, during shaping first mould, wild phase cavity block does not place matrix, obtains a SPC matrix; The plastics capacity of the first mould is greater than in wild phase cavity block amount when placing matrix;

2) the second mould starts, and the plastics capacity of injection machine is set to normal level, and before each matched moulds, the SPC matrix handled well is placed in wild phase die cavity, the grooved surface of SPC matrix is towards solid plate direction; Often inject and once obtain a SPC exemplar and a SPC matrix.

Effect of the present invention and benefit are: 1) first lay prefabricated reinforcement fiber with traditional, again that matrix material is different from the method that reinforcement compound prepares composite, the first injection mo(u)lding matrix of this method, then utilizes co-injection molding mode directly to prepare reinforcement fiber in the base; 2) structure and the size that change groove on matrix can adjust flexibly to the size of reinforcement fiber and structure; 3) change injection parameters, the microscopic characteristics such as the degree of molecular orientation of reinforcement and matrix, degree of crystallinity can be adjusted, thus can more flexibly and easily the performance of single polymer composites be regulated and controled; 4) can the injection mold structure of simultaneously shaping single polymer composites precast body and reinforcement, utilize one set of die and former can directly prepare single polymer composites reinforcement material need not be laid in advance; 5) in the method, Material selec-tion is wide in range, does not require that the fusing point of matrix material is lower than the fusing point of wild phase material.

Accompanying drawing explanation

Fig. 1 (a) is self-reinforcing injection forming mold assembling front view altogether in a kind of SPC mould.

Fig. 1 (b) is self-reinforcing injection forming mold assembling plan view altogether in a kind of SPC mould.

Fig. 2 (a) is the occurring matrix type cavity insert front view that SPC is total to injection forming mold.

Fig. 2 (b) is the occurring matrix type cavity insert top view that SPC is total to injection forming mold.

Fig. 3 (a) is the wild phase cavity block front view that SPC is total to injection forming mold.

Fig. 3 (b) is the wild phase cavity block top view that SPC is total to injection forming mold.

In figure: 1 Bottom clamp plate; 2 push pedals; 3 thimble fixed heads; 4 dynamic model backing plates; 5 moving platens; 6 occurring matrix type cavity inserts; 7 water are chewed; 8 solid plates; 9 top clamping plates; 10 wild phase cavity block.

Detailed description of the invention

The technical process of preparation SPC of the present invention is described in detail below in conjunction with technical scheme and accompanying drawing 1 (a), (b) and 2 (a), (b).

1) by the occurring matrix type cavity insert 6 in accompanying drawing 2 and the shaping insert 10 of enhancement mode, be installed on moving platen 5 by alignment pin and soket head cap screw; The moving platen 5 and solid plate 8 of mould are provided with cooling water hole, utilize die heater to control the temperature of mould in forming process, this just constitutes self-reinforcing in mould and is total to the mould of injection mo(u)lding SPC;

2) set the molding parameter of injection machine, be expelled in mold cavity by the polymer plastified, during shaping first mould, owing to not having matrix in wild phase insert, so only can obtain a SPC matrix, the plastics capacity of the first mould should suitably be heightened;

3) cut by the material of the shaping SPC matrix exemplar obtained handle, before matched moulds, be placed into by the matrix handled well in the wild phase forming recess of mould, the grooved surface of matrix is towards solid plate direction;

4) from the second mould, suitably reduce the plastics capacity of injection machine, operation injection machine, completes injection moulding process;

5) from the second mould, often inject and once can obtain a SPC exemplar and a SPC matrix;

The present invention includes but be not limited to above embodiment, every any equivalent replacement of carrying out under the spirit and principles in the present invention or local improvement, all will be considered as within protection scope of the present invention.

Claims (1)

1. a self-reinforcing injection molding forming method altogether in single polymer composites mould, is characterized in that:

In single polymer composites mould of the method, the common injection molding apparatus of self-reinforcing comprises top clamping plate, solid plate, moving platen, occurring matrix type cavity insert, wild phase cavity block and Bottom clamp plate; Moving platen has two independently grooves, be respectively used to install wild phase cavity block and occurring matrix type cavity insert, two inserts, by straight pin and side location, use bolt to be arranged on moving platen; Occurring matrix type cavity insert has along filling melt direction, has three projections of constant cross-section, for the preparation of the SPC matrix with groove structure; The die cavity of wild phase cavity block is rectangular structure, and size is identical with the contour dimension of SPC matrix, for the filling of SPC wild phase in body trench; Shaping step is as follows:

1) set the molding parameter of injection machine, be expelled in mold cavity by the polymer plastified, during shaping first mould, wild phase cavity block does not place matrix, obtains a SPC matrix; The plastics capacity of the first mould is greater than in wild phase cavity block amount when placing matrix;

2) the second mould starts, and the plastics capacity of injection machine is set to normal level, and before each matched moulds, the SPC matrix handled well is placed in wild phase die cavity, the grooved surface of SPC matrix is towards solid plate direction; Often inject and once obtain a SPC exemplar and a SPC matrix.