Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B28—WORKING CEMENT, CLAY, OR STONE
  • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
  • B28B23/00—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects
  • B28B23/0006—Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objects the reinforcement consisting of aligned, non-metal reinforcing elements

Definitions

• the present invention relates to a process for the preparation of manufactured products based on hydraulic binders, provided with a reinforcement of a fibrilled synthetic polymeric material.
• the present invention provides a process for preparing a manufactured product based on a hydraulic binder and containing a reinforcement of fibrilled film of synthetic polymeric material, characterized by comprising:
• operations (a) and (b) may be carried out simultaneously; operations (c) and (d) may likewise be carried out simultaneously:
• the assembly thus obtained by operation (d) or by the combination of operations (c) and (d) may be subjected to a treatment under vacuum in order to eliminate any possible excess of water .
• a series of operations (a) to (d) may be repeated on the non-compressed product obtained from a preceding series of operations (a) to (d), until there is obtained a manufactured product, for example a plate, of the required thickness, the compression operation (e) being subsequently applied to obtain the finished or end product.
• the vacuum treatment may be carried out at the end of each series of operations (a) to (d), or before the final compression operation (e).
• the fibrilled.films usable in the present invention may be made of any orientable synthetic polymer, and may be prepared according to various different techniques, the most important of which comprises fissuring or splitting a mono-oriented film by means of heated reliefs, points or blades, and by stretching the film thus obtained crosswise, thus conferring to it a net-like structure.
• the film may also incorporate a suitable filler, such as a zirconium compound, a diatomite, or a cement mix, as described in Italian patent application Nos. 26463/79 and 26861/79.
• a suitable filler such as a zirconium compound, a diatomite, or a cement mix, as described in Italian patent application Nos. 26463/79 and 26861/79.
• All known hydraulic binders such as Portland cements, aluminous cements, hydraulic limes, and chalk, may be used in the process of the present invention.
• One advantage of the process according to the present invention in comparison with the preparation from aqueous mixes of binders, is that of using only the quantity of water necessary for the development of the hydration of the binder, or a quantity only slightly greater, and consequently a considerable reduction in the installation costs and the energy consumption of the process may be achieved.
• the number of superimposed fibrilled films, used in one distribution of the hydraulic binder according to operation (a), is preferably from 2 to 100.
• the quantity by weight of fibrilled film utilized is preferably from 2% to 7.5% by weight of the weight of the hydraulic binder, considered in the dry state.
• the quantity of the water added in the operation (c) is preferably from 12% to 30% by weight based on the weight of the binder in the dry state.
• This package was then placed into a suitable mold and strewn with Portland cement powder by means of a powder-dispenser which, according to known techniques, spread uniformly over the whole 50x50 cm plane a quantity of 650 g of cement, while simultaneously carrying out a slight vibratory motion to promote easy penetration by the cement powder into the package
• the water was additioned with a cement super-fluidizer (Melment 10 of SKW in a 20% concentration) in a ratio of 13 g per 130 cc of water.
• a cement super-fluidizer Melment 10 of SKW in a 20% concentration
• the assembly thus obtained was subjected to lateral vibrations by means of mechanical vibrators, and to a downward compacting action with a compacting blade connected to a vibrator according to known techniques in the field of cement processing.
• the assembly was subjected to a vacuum of 200 mmHg for about 1 minute, thereby extracting 200 cc of water; the impregnated plate formed was thereupon removed from the mold, compressed at a pressure of 45 kg/s q .cm and finally allowed to age and harden for 28 days.
• the flexural strength of the obtained hardened plate was then measured, according to the UNI 3948 method, thereby obtaining unitary flexural strength values equal to 348 kg/sq.cm lengthwise (or in the direction of the fissuring of the fibrilled film), and equal to 115 kg/cm 2 crosswise.
• the package was formed by a total of 40 nets, arranged in groups or batches of 10 nets with their main reticular axes, derived from the fibrillation, at 90 to each other, so as to impart to the cement plate to be prepared a mechanical isotropy.
• the package was then dispersed uniformly with 1730 g of dry Portland cement powder as in the preceding example; the mold was then subjected to a slight vibration in order to facilitate penetration of the cement into the meshes of the nets.
• the mold was then subjected to a vacuum of about 200 mmHg for about 1 minute, removing thereby about 100 cc of water and thus reducing the excess water contained in the net-cement mass to about 13% of the cement.
• the plate was then compressed under a pressure of 45 kg/sq.cm and was then allowed to age and harden for 28 days.
• the flexural strength at break of the hardened plate, about 4 mm thick, was then measured and found to be equal to 338 kg/sq.cm in one direction and to 345 kg/sq.cm in the orthogonal direction.

Landscapes

• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Chemical & Material Sciences (AREA)
• Ceramic Engineering (AREA)
• Mechanical Engineering (AREA)
• Preparation Of Clay, And Manufacture Of Mixtures Containing Clay Or Cement (AREA)
• General Preparation And Processing Of Foods (AREA)

Applications Claiming Priority (2)

Publications (3)

Family

ID=11217671

Family Applications (1)

Country Status (6)

Cited By (2)

Family Cites Families (7)

• 1980
  • 1980-11-05 IT IT25768/80A patent/IT1141089B/it active
• 1981
  • 1981-11-04 DE DE8181305249T patent/DE3176447D1/de not_active Expired
  • 1981-11-04 YU YU02621/81A patent/YU262181A/xx unknown
  • 1981-11-04 DK DK488381A patent/DK488381A/da unknown
  • 1981-11-04 EP EP81305249A patent/EP0051498B1/fr not_active Expired
  • 1981-11-04 ES ES506825A patent/ES8302524A1/es not_active Expired

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