A kind of hollow bamboo base fiber compound structure material and manufacture method thereof
Technical field
The invention belongs to the wood-based plate in industry of artificial boards and manufacturing technology field thereof, be particularly useful for mechanical property requirements high, building and the Engineered Wood Products such as the beam that specification is large, post, furniture and floor.
Background technology
Bamboo base fibrous composite is by bamboo wood after discongesting and forming fibrillatable Bamboo veneer, a kind of novel building processed through operations such as super-dry, impregnations, again drying, assembly and gummed and Engineered Wood Products.The MOR of this material can reach more than 350MPa, hot strength can reach more than 360MPa, compressive strength can reach more than 140MPa, elastic modelling quantity can reach 27GPa [Yu Wenji. the progress [J] of China's high-performance bamboo base fibrous composite. timber industry, 2011,25 (1): 6-8,29], there is good physical and mechanical property, bamboo base fibrous composite is directly used in and manufactures beam, post, furniture and floor etc., often cause intensity superfluous, cause waste; In the process of composition, the density of this material reaches 1.05 ~ 1.30g/cm
3, because material deadweight is larger, easily causes and use inconvenience.
Secondly, the production technology of bamboo base fibrous composite is mainly divided into two large classes: a class is cold forming, heat curing process, is called for short cold-press process; Two is use for reference wood-based plate conventional thermocompression technique, the bamboo base fibrous composite heat pressing process of formation.Due to the restriction of the specification by cold press and hot press device, at present, the specification of bamboo base fibrous composite is all less, and the specification (long × wide × thick) that the bamboo base fibrous composite square stock as cold-press process production is conventional is: 193cm × 10.5cm × 15.0cm and 200cm × 14.5cm × 15.0cm; The bamboo base fibrous composite stock size (long × wide × thick) that heat pressing process is produced is: 244cm × 122cm × (1.5-4) cm, maximum breadth also can only reach 500cm × 120cm × 5cm (Yu Wenji, China's bamboo base fibrous composite industry development situation and trend is analyzed, timber industry, 2012,26 (1): 11-14).Such specification is difficult to meet the dimensional requirement of structural wood as beam, post, large-scale furniture and large gauge floor.
Moreover the structural wood of large gauge adopts Lengthwise joint by the material of small dimension usually, laterally spells wide, and the splicing of restructuring compound forms.Glued joint the decline that bad meeting causes plate property, glued joint common defect type and comprise: come unstuck, crack, space, bondline thickness variation, solidification incomplete sum surface preparation defect etc., wherein, come unstuck, crack and surface preparation defect be main.The principal element affecting adhesive bonding of composites intensity has: the impact of the factors such as the material category of connected piece, the ratio of rigidity of connected piece and thermal coefficient of expansion, make by the rigidity approximately equal of bonded part whenever possible as far as possible, thermal coefficient of expansion (beneficial little Su close to hygroscopic expansion coefficient, composite handbook, Chemical Industry Press, 2009).
Chinese patent 201010243351.7,201020279829.7,201020279815.5 provide a kind of undersized log that adopts manufactures undersized log recombination structure material and manufacture method thereof by finger or mitered, adopts the recombination structure material that undersized log can be processed into large gauge in this way.But the glue-line that this technique is formed when secondary gluing, its glue performance is unstable, and have certain variability, phenomenons such as ftractureing, come unglued may appear in some sheet material glue-lines; Then may there is the problems such as bonding strength is low, the physical mechanics property loss of energy is large in other sheet materials.By analyzing, the main cause of above-mentioned phenomenon and problem is caused to be that spot gluing is bad.
According to previous research: the prerequisite forming good splicing is that adhesive molecule can fully contact and effective wetting (Gu Jiyou, adhesive and coating, China Forestry Publishing House, 1999) with by splicing material (timber).Bamboo base fibrous composite is that a kind of by porous natural material timber or bamboo wood, at larger pressure, (cold-press method briquetting pressure is about 60MPa, pressure sintering briquetting pressure is 4 ~ 6MPa) act on compacted under, the density of bamboo base fibrous composite is generally greater than 1.0g/cm
3when environment temperature and humidity change, the distortion such as easement, crosswise concaving, warpage can be there is, can produce time serious and jump the phenomenon such as silk and cracking (Yu Wenji, China's bamboo base fibrous composite industry development situation and trend analysis, timber industry, 2012,26 (1): 11-14), even if adopt sanding process in process, be also difficult to obtain smooth cemented surface, secondly, in the manufacture process of bamboo base fibrous composite, more even in order to make adhesive distribute, usual employing dipping method, bamboo bundle and wood bundle are by after impregnation, and its surface all attached to one deck adhesive, after solidification, define the glue-line of the insoluble not molten densification of one deck, surface wettability declines, moreover, bamboo base fibrous composite intensity is high, hardness is large, be difficult to be compressed, but be subject to the impact of Traditional Thinking, when selecting bonded part, select rigidity approximately equal as far as possible, the material that thermal expansion is close with moisture expantion, usually can not consider to introduce the third material except adhesive, therefore, coarse surface, be difficult to the splicing face compressed and bad wetability easily produces in post forming process and comes unstuck, crack, space, the adhesive defects such as bondline thickness variation, particularly the bad problem of bamboo base fibrous composite spot gluing of high rigidity fails effectively to be solved all the time.
Summary of the invention
The object of the invention is to improve the deficiency in existing technology, hollow bamboo base fiber compound structure material is provided, makes its physical and mechanical property meet the requirement of structural wood performance.
For achieving the above object, the present invention takes following technical scheme:
The invention provides a kind of hollow bamboo base fiber compound structure material, its bag two pieces of front plate, two pieces of side panels, veneer and adhesives, it is characterized in that: two pieces of front plate and two pieces of side panels compose the hollow square column that cross section is square or rectangular mutually, and described front plate and side panel are bamboo base fibrous composite; Arrange one deck veneer between described mutual gummed two pieces of front plate and side panel junction, the thickness of described veneer is 0.1-1.5mm; Be provided with adhesive layer between bamboo base fibrous composite and veneer, adhesive used is the agent of resorcinol gluing or aqueous solution acrylate resin; The weld of described mutual gummed two pieces of front plate and two pieces of side panels is an angle of 90 degrees or miter angle.
Described a kind of hollow bamboo base fiber compound structure material, it is characterized in that: the front plate of hollow bamboo base fiber compound structure material and side panel are formed through Lengthwise joint by bamboo base fibrous composite, the composition surface of Lengthwise joint is provided with adhesive layer, and adhesive used is the agent of resorcinol gluing or aqueous solution acrylate resin.
Described a kind of hollow bamboo base fiber compound structure material, also include cardboard, it is characterized in that: the bamboo base fibrous composite of described Lengthwise joint is provided with a layer paperboard between the composition surface of Lengthwise joint, be provided with adhesive layer between bamboo base fibrous composite and cardboard, adhesive used is the agent of resorcinol gluing or aqueous solution acrylate resin.
Described hollow bamboo base fiber compound structure material, is characterized in that: described spreading is finger spreading or mitered spreading.
The invention provides a kind of manufacture method of hollow bamboo base fiber compound structure material, comprise following workshop section: (one) raw material prepares, (two) recombinate compound, (three) post-processed, it is characterized in that:
(1) raw material prepares, and comprises the preparation of bamboo base fibrous composite, veneer prepares and adhesive is allocated:
(1) bamboo base fibrous composite prepares, and by discongesting, drying, impregnation, again drying, gummed, maintenance, cutting edge, saw cut and sanding workshop section, bamboo processing become specification bamboo base fibrous composite; Be impregnating phenolic resin at the adhesive that impregnation operation is used;
(2) certain thickness bamboo base fibrous composite is cut into 4 blocks of same widths bamboo base fibrous composite laths, the lath both sides of each bamboo base fibrous composite are mitered into the inclined-plane of miter angle or the right-angle surface of an angle of 90 degrees, as two pieces of front plate and two pieces of side panels;
(3) veneer prepares, and by rotary-cut, drying and cutting edge workshop section, timber is processed into the veneer that thickness is 0.1-1.5mm; Veneer prepares, and by rotary-cut, drying and cutting edge workshop section, timber is processed into the veneer that thickness is 0.1-1.5mm; Glued joint if weld presses miter angle, veneer is cut into width for the bamboo base fibrous composite thickness 1.5 times described in step (2); Glued joint if weld presses an angle of 90 degrees, veneer is cut into width for the bamboo base fibrous composite thickness 1.1 times described in step (2);
(4) adhesive allotment, by the host of the agent of resorcinol gluing or aqueous solution acrylate resin and curing agent according to 100: (10-20) ratio uniform mixes;
(2) restructuring compound
Described veneer upper and lower surface is coated the agent of resorcinol gluing or aqueous solution acrylate resin, described two pieces of front plate and two pieces of side panels are combined, through composing the hollow square column that cross section is square or rectangular by for miter angle or an angle of 90 degrees at mutual glue joint; Between described mutual gummed two pieces of front plate and side panel connect, one deck veneer is set, obtains hollow bamboo base fibrous composite slab.
(3) post-processed
By described hollow bamboo base fiber compound structure material slab, cut and sanding workshop section through cutting edge, saw, be processed into hollow bamboo base fiber compound structure material.
The manufacture method of described hollow bamboo base fiber compound structure material, comprise following Lengthwise joint workshop section, it is characterized in that: described specification bamboo base fibrous composite two ends are adopted and is machined into finger face or miter, resorcinol gluing agent again after allotment is coated in finger face or miter or aqueous solution acrylate resin, make the bamboo base fibrous composite of Lengthwise joint through longitudinal finger or mitered.
The manufacture method of described hollow bamboo base fiber compound structure material, it is characterized in that: in described Lengthwise joint workshop section, the bamboo base fibrous composite of described Lengthwise joint is provided with a layer paperboard between the composition surface of Lengthwise joint, be provided with adhesive layer between bamboo base fibrous composite and cardboard, adhesive used is the agent of resorcinol gluing or aqueous solution acrylate resin.
The manufacture method of described hollow bamboo base fiber compound structure material, it is characterized in that: in mitered operation, the thickness at mitered position and chamfer length ratio are 1: 10-1: 20.
Described hollow bamboo base fiber compound structure material, it is characterized in that: in finger operation, box pin joint parameter: the long 8mm-45mm of tooth, tooth top width 0.5mm-20mm, tooth pitch 3mm-20mm, tooth refers to gradient 1/6-1/9.
Hollow bamboo base fiber compound structure material provided by the invention, adopt hollow square column structure, reduce the density of material significantly, production technology is simple; Reduce costs; The ratio of strength to weight is large.
In addition, arrange between the bamboo base fibrous composite that, strength and stiffness high in hardness are large one deck compressible, can deformation, thickness 0.1-1.5mm veneer veneer, this splicing face structural design, take full advantage of the good wetability of veneer, permeability, gummed and compressible and can the characteristic such as deformation, utilize veneer veneer deformation behavior, effectively can fill up due to the gap that cemented surface injustice is formed between hardness is high, strength and stiffness are large bamboo base fibrous composite, thus add effective cemented surface; Utilize wetability and gummed property that veneer veneer is good, good cemented surface can be formed with bamboo base fibrous composite, improve glue performance; When secondary gluing, utilize permeability and the compression performance of veneer, under the effect of applied pressure, make veneer veneer compression compact, simultaneously, enable the agent of resorcinol gluing or aqueous solution acrylate resin penetrate in veneer veneer fully, occur to glue together with veneer veneer and react, thus form the compressed wood with bamboo base fibrous composite similar nature.This splicing face structural design, make use of the characteristic of bamboo base fibrous composite and veneer veneer dexterously, the large gauge bamboo base fibrous composite bonding layer after gummed is made to meet the rigidity approximately equal of bonded part, the traditional classical splicing face gummed theory that thermal expansion is close with moisture expantion, solves again the adhesive defects such as bamboo base fibrous composite comes unstuck, crack, space, bondline thickness variation.
Hollow bamboo base fiber compound structure material provided by the invention, when Lengthwise joint, is provided with a layer paperboard between the composition surface of Lengthwise joint, and cardboard is substantially identical with above-mentioned veneer veneer in the effect of weld, repeats no more here.Why when Lengthwise joint, select cardboard, reason is as follows: compared with veneer veneer, and except good wetability, permeability, gummed and compressible and can except the characteristic such as deformation, flexibility and the plasticity of cardboard are better.Be often referred to junction and miter is special-shaped curved, cardboard can design according to the shape of finger face and miter, thus the splicing face of making is more identical, can reduce to greatest extent come unstuck, crack, space, the adhesive defect such as bondline thickness variation.
Hollow bamboo base fiber compound structure material provided by the invention is in Lengthwise joint and restructuring recombination process, adopt Cold-setting adhesives i.e. two component isocyanate adhesive or resorcinol adhesive, according to the needs of target product in length and thickness direction restructuring compound, the large-sized specification requirement of structural wood can be met.
Hollow bamboo base fiber compound structure material provided by the invention, in bamboo base fibrous composite manufacture process, select impregnating phenolic resin or dipping Lauxite, make bamboo bundle or wood bundle reach even impregnation, thus obtain the bamboo base fibrous composite of stable performance.
Below in conjunction with the drawings and specific embodiments, the invention will be further described, not limitation of the present invention, and the equivalent replacement of every any this area of carrying out according to the disclosure of invention, all belongs to protection scope of the present invention.
Accompanying drawing explanation
Fig. 1 bamboo base fibrous composite finger face
Fig. 2 cardboard finger face
Fig. 3 bamboo base fibrous composite finger spreading
Bamboo base fibrous composite after Fig. 4 finger spreading
Fig. 5 veneer
Fig. 6 weld is an angle of 90 degrees hollow bamboo base fiber compound structure material slab
Fig. 7 weld is an angle of 90 degrees hollow bamboo base fiber compound structure material (profile)
Fig. 8 weld is an angle of 90 degrees hollow bamboo base fiber compound structure material
Fig. 9 bamboo base fibrous composite oblique section
Figure 10 cardboard oblique section
Figure 11 bamboo base fibrous composite mitered spreading
Bamboo base fibrous composite after Figure 12 mitered spreading
Figure 13 weld is miter angle hollow bamboo base fiber compound structure material slab
Figure 14 weld is miter angle hollow bamboo base fiber compound structure material (profile)
Figure 15 weld is miter angle hollow bamboo base fiber compound structure material
Detailed description of the invention
Embodiment 1: weld is an angle of 90 degrees hollow bamboo base fiber compound structure material
The hollow bamboo base fiber compound structure material of exemplary embodiments of the present invention, it comprises the bamboo base fibrous composite (1) of longitudinal finger spreading, cardboard (2), veneer (3) and adhesive (not marking in figure), as shown in Figure 8, it is square hollow square column that two pieces of front plate and two pieces of side panels compose cross section mutually, and front plate (11) and side panel (12) are bamboo base fibrous composite; Glue together and arrange one deck veneer (3) between two pieces of front plate and side panel junction, the thickness of veneer (3) is 1.2mm; Be provided with adhesive layer between bamboo base fibrous composite (1) and veneer (3), adhesive used is the agent of resorcinol gluing or aqueous solution acrylate resin; The weld of mutual gummed two pieces of front plate (11) and side panel (12) is an angle of 90 degrees.
Hollow bamboo base fiber compound structure material manufacture method typical case implementation step of the present invention is as follows:
1, by discongesting, drying, impregnation, again drying, gummed, maintenance, cutting edge, saw cut and sanding workshop section, bamboo processing become (long × wide × thick) be: the bamboo base fibrous composite of 220cm × 20cm × 3.0cm; The adhesive used in impregnation operation is impregnating phenolic resin, in hot pressing process, adopts pressure sintering to produce bamboo base fibrous composite, belongs to prior art;
2, by above-mentioned bamboo base fibrous composite by tooth milling machine milling one-tenth finger joint teeth as shown in Figure 1, the long 25mm of tooth, tooth top width 10mm, tooth pitch 20mm, tooth refers to gradient 1/8.
3, take resorcinol gluing agent host and curing agent according to 100: 15 ratios, mixing, after stirring, form host and the agent of curing agent uniform resorcinol gluing;
4, cardboard is processed into dentalation as shown in Figure 2, the long 25mm of tooth, tooth top width 10mm, tooth pitch 20mm, tooth refers to gradient 1/8.
5, the resorcinol gluing agent after described allotment is coated in finger face, glue-spread is 300g/m
2, or according to the area am before cardboard processing
2, adopt impregnation mode, enter in adhesive by cardboard finger, impregnation resin content is (300 × a) g; By the bamboo base fibrous composite finger-jointed plate after gluing according to assembly shown in Fig. 3, adopt two ends to overstock to centre the sheet material after assembly, finger place is combined closely, and the sheet material after finger spreading as shown in Figure 4.
6, by rotary-cut, drying, cutting edge workshop section, timber being processed into width is 33cm, and thickness is the veneer bar of 1.0mm, as shown in Figure 5;
7, the resorcinol gluing agent after allotment coated by veneer, glue-spread is 300g/m
2;
8, described two pieces of front plate and two pieces of side panels being pressed at mutual glue joint is an angle of 90 degrees combination, between mutual gummed two pieces of front plate and side panel connect, one deck veneer is set, by assembly shown in Fig. 6, being square or rectangular hollow square column through composing cross section, obtaining hollow bamboo base fiber compound structure material slab.
9, by described hollow bamboo base fiber compound structure material slab, to cut through cutting edge, saw, the workshop section such as sanding, be processed into hollow bamboo base fiber compound structure material as shown in Figure 7 and Figure 8.
Embodiment 2: weld is miter angle hollow bamboo base fiber compound structure material
The hollow bamboo base fiber compound structure material of exemplary embodiments of the present invention, it comprises the bamboo base fibrous composite (1) of longitudinal mitered spreading, cardboard (2), veneer (3) and adhesive (not marking in figure), as shown in figure 15, it is square or rectangular hollow square column that two pieces of front plate and two pieces of side panels compose cross section mutually, and front plate (11) and side panel (12) are bamboo base fibrous composite; Glue together and arrange one deck veneer (3) between two pieces of front plate and side panel junction, the thickness of veneer (3) is 1.0mm; Be provided with adhesive layer between bamboo base fibrous composite (1) and veneer (3), adhesive used is aqueous solution acrylate resin; The weld of mutual gummed two pieces of front plate (11) and side panel (12) is miter angle.
Hollow bamboo base fiber compound structure material manufacture method typical case implementation step of the present invention is as follows:
1, by discongesting, drying, impregnation, again drying, gummed, maintenance, cutting edge, saw cut and sanding workshop section, and timber being processed into (long × wide × thick) is: the bamboo base fibrous composite of 180cm × 140cm × 4cm; The adhesive used in impregnation operation is impregnating phenolic resin, in gluing technique, adopts cold-press method, belongs to prior art;
2, the both sides of above-mentioned bamboo base fibrous composite are mitered into the inclined-plane of miter angle;
3, above-mentioned bamboo base fibrous composite two ends are sawn into oblique section as shown in Figure 9, the thickness at mitered position and chamfer length ratio are 1: 10;
4, take according to 100: 18 ratios host and the curing agent that emulsion polymer isocyanate adhesive sticks agent, mixing and stirring;
5, by cardboard by being processed into ramp structure as shown in Figure 10, the thickness at mitered position and chamfer length ratio are 1: 10;
6, the emulsion polymer isocyanate adhesive after miter coats described allotment sticks agent, and glue-spread is 250g/m
2, or according to the area am of cardboard miter
2, adopt impregnation mode, immersed by cardboard in adhesive, impregnation resin content is (250 × a) g; By the bamboo base fibrous composite after gluing according to assembly shown in Figure 11, adopt two ends to overstock to centre the sheet material after assembly, mitered place is combined closely, and the sheet material after mitered spreading as shown in figure 12.
7, by rotary-cut, drying, cutting edge workshop section, timber being processed into width is 6cm, and thickness is the specification veneer of 0.8mm, as shown in Figure 5;
8, the emulsion polymer isocyanate adhesive after allotment coated by veneer sticks agent, and glue-spread is 250g/m
2;
9, described two pieces of front plate and two pieces of side panels being pressed at mutual glue joint is miter angle combination, between mutual gummed two pieces of front plate and side panel connect, one deck veneer is set, by assembly shown in 13, being square or rectangular hollow square column through composing cross section, obtaining hollow bamboo base fiber compound structure material slab;
10, by described hollow bamboo base fiber compound structure material slab, to cut through cutting edge, saw, the workshop section such as sanding, be processed into hollow bamboo base fiber compound structure material as shown in Figure 14 and Figure 15.