Title of Invention	"POLYMER CEMENT COMPOSITE FOR LANDING PLATFORM"
Abstract	A polymer cement composite for preparing landing platforms comprising melamine formaldehyde resin, guargum and cementitious material and a process for preparing the same.

Full Text

FIELD OF INVENTION The present invention relates to a polymer cement composite for preparing landing platform and the process thereof. BACKGROUND Hovercraft skirt segments near the sea shore are prone to failure. The skirt segment is one of the most design sensitive parts of a hovercraft. If not right the skirt can be damaged very easily since it encounters the obstacles. The skirts material needs to be light, flexible and durable. The frequent movement of hovercraft for landing always poses a problem for the deployment areas of operation due to the loose and abrasive nature of sea sand. The condition of sea shore leads to frequent tearing of base cloth made of Polyamide yarn nylon 6 / nylon 66 along with rubber. The life of skirt segment made of above material composition is reduced to lesser than 150 hours despite its guaranteed life of 500 hours. The skirt segment becomes delaminated and torn within 100 to 150 hours of use. It has been observed that the vessel's initial hovering and switching off period are the critical time. During this period bottom surface of the skirt part of the hovercraft near landing pads undergoes rubbing with abrasive sand, stones and gravels vigorously leading to skirt failure and rapid costly replacements. Therefore cost effective, rapid and easily constructed hovercraft landing platform with the capability of handling smooth operation of the vessel are required at the sea shore. Presently no hovercraft landing platforms are available on sea shores. Only reinforced cement concrete structure can be built depending upon available sea shore area. At sea shore or delegated beach areas, construction of platform, slipway and other military structures by conventional methods like reinforced concrete (RCC) require considerable time and it is not an easy process to accomplish in short time period. It requires large quantity of cement, concrete and bitumen, good quality water, construction equipments and skilled man power. In the operational coastal areas, construction and repair of these military structures can not be achieved in a short time due to non availability of the above resources. In addition, the coastal zones and the topography is such that making reinforced concrete construction is not feasible due to higher costs involved on soil testing, anti-corrosive measures while constructing rams, minimum area of sea shore availability and erosion nature of sea in the particular places where these hovercrafts are positioned. The guar plant is a pod bearing, nitrogen-fixing legume, grown annually in arid and semiarid regions of Indian subcontinent, where it acts as a food and water store. Guargum is extracted from the seed of the leguminous shrub Cyamopsis tetragonoloba. It is a galactomannan consisting of a (1-4)-linked ft-D-mannopyranose backbone with their 6th positions linked to a galactose. There are 1.5 -2 mannose residues for every galactose residue. The literature survey revealed rapid preparation of helipad by spraying grade guar-gum developed in the desert areas for military operations. Hence the purpose of the present invention is to develop a smooth landing platform that can be made very easily by spraying technique in the coastal areas, but this material should not be affected by sea water flows OBJECTIVE OF THE INVENTION The object of the present invention is to prepare a polymer cement composite using melamine formaldehyde and guargum. Another object of the present invention is to prepare a cost effective, rapid and easily constructible landing platform. Yet another object of the present invention is to prepare a polymer cement composite with high compressive strength and good load bearing capacity. Still another object of the present invention is to prepare a polymer cement composite with high thermal stability. SUMMARY OF THE INVENTION The present invention relates to a polymer cement composite for preparing landing platforms comprising: - Melamine formaldehyde resin - Guargum and - Cementitious material. The present invention further relates to a process for the preparation of the polymer cement composite for preparing landing platforms comprising - mixing melamine formaldehyde resin and guargum in a 1:1 ratio including the cementitious material to obtain a homogenous mixture, - Preparing a slurry of the homogenous mixture in step (i) in water, Pouring or spraying the said slurry on ground, Drying said slurry. DETAILED DESCRIPTION The present invention relates to the preparation of a guargum based polymer cement composite. Tailoring of materials for applications becomes important where a good balance between engineering properties and material weight/cost is required. Polymer based composites offer many advantages over conventional cements. In order to meet the requirements of the rapid construction of hovercraft landing platforms at sea shore various compositions of oxychloride cement along with sea sand, melamine formaldehyde resin, guar gum and unsaturated polyester resins were prepared for optimization of the suitable composition with optimum compressive strength. Various cubical specimens of size 27 cm3 and 1000 cm3 were prepared and examined for smoothness of their molded surfaces and compressive strengths. Various parameters of the compositions of oxychloride cement along with sea sand, melamine formaldehyde polymeric resin, guar gum polysaccharide and unsaturated polyester, namely compressive strength, flexural strength and durability under sea water were determined. Based on the results obtained further optimization was progressed. Experimentation with various mix designs is generally done by specifying desired "workability" as defined by a given slump and a required 28 days compressive strength. The characteristics of the coarse and fine aggregates determine the water demand of the mix in order to achieve the desired workability. The 28 day curing studies, sea water exposure is done after determination of the correct amount of cementitious material to achieve the required water-cement ratio along with the aggregate in order to achieve optimum ultimate compressive strength. In one of the embodiments of the invention the percentage composition of the ingredients of the polymer composite cement is as follows : 6-8% magnesium oxychloride cement, 3-5% fly ash, 1-5% melamine formaldehyde resin, 1-2% of guargum along with sea sand. The melamine formaldehyde resin and low viscosity guargum were taken in a 1:1 ratio. The aim of this study was to improve the composite strength of the selected polymer cement composite along with sea sand. The method chosen to achieve above aim was to formulate polymer cement composites primarily using melamine formaldehyde(MF) and guar gum. MF resin gives excellent adhesive performance, good moisture resistance and tends to give lower formaldehyde emission than UF resin. Guar gum and MF combination with magnesium-oxychloride cement are suitable for compressive moulding and very good load bearing capacity for hovercrafts. Physical properties were determined on specimens prepared under laboratory conditions. Their miscibility with each other, thermal stability, compressive and impact strength were characterized. Actual field conditions may vary and yield different results. The 1% MF and 1% Low viscosity Guar gum mixed with magnesium oxychloride cement (OCC) were found to significantly increase the compressive strength of the composite up to 221.02 kg/cm2 using a high molecular weight sea sand. In addition the hydroxyl groups (OH) available on the hydrocolloids (example: three hydroxyl groups in one glucose ring of the galactomannan ) from the hydrogen bonding with the inorganic part of the cement / sand / mortar that is OH - Si - OH part, that leads to further curing and strengthening of the mortar cement or the grout. The set having 1% Guar gum 1% MF composite along with the magnesium oxy chloride cement is the combination that shows an increase in strength, thermal stability and the required suitability for hovercraft landing at sea shore. The polymeric combination can also be intercalated with the neoprene rubber and Nylon 6, 66 yarns to improve the wear resistance of the Hovercraft Skirt segment as it shows the water resistance and better impact strength with low density for flotation. Process for the preparation of landing platform The polymer composite was prepared by mixing melamine formaldehyde resin, guargum, magnesium oxychloride cement, fly ash and sea sand to obtain a homogenous mixture. Thereafter a slurry of the said mixture was prepared with optimum quantity of water. The viscosity was maintained between 200-500cps. The slurry or the grouting mixture is then either sprayed or poured over the rough ground surface and dried for about 12 hours to obtain a landing platform with high compressive strength Trials Before making the landing platform for the Coast Guard hovercraft 1%GG,1% MF composition along with magnesium oxychloride cement and fine sea sand composite was tested for an indigenously developed hovercraft. The vessel is having 250 kg weight, 16 feet length and 08 feet breadth. The weight ratio of 109 Coast Guard hovercraft (25000 kg) and the indigenously developed hovercraft (250 kg) found to be 10:1. With the concurrence of the designer of the hovercraft field test of the polymer based composite was carried out. Westergaard theory was used to optimize the thickness of platform. Based on the set of formulas using Excel program by interpolation suitable thickness was selected. To find out suitable thickness of platform, the calculation is as follows: where S = stress, psi; W = wheel load, Ibs. d = slab thickness, in. Here, for the calculation of thickness of concrete Total weight of desi hovercraft, ie, W=250 Kg = 551.25 Ibs. where 1 Kg = 2.205 Ibs. Achieved compressive strength [ 1%Guargum 1% MF mould ] 'S' = 14.37 MPa 1 MPa=145 PSI and S= 2083.65 PSI Hence thickness (d) = 0.7127 inches = 1.81 cm. A 1% MF and 1% GG polymer composite concrete platform having two cm thickness as per the above mentioned calculations for carrying out small scale field test was made with the quantity of composition mentioned in table 1.1. The mixed polymer mortar was applied on the stabilized surface. For stabilization, the grouting mixture of above composition was poured. A sample 10cm3 mould was also made out of this composition and tested for compressive strength. It was found 14.5MPa / 147.76 Kg/cm2. For further curing of the Polymer Cement Concrete Composite additional water curing was not required. After 12 hours the hovercraft was allowed to land and hover above the platform. The platform and skirt areas were inspected subsequently for 9 months and found to remain smooth. No cracks were developed on the surface of platform. There was no deteriorating effect on the platform because of continuous heavy rains and the water piling over for 5-6 months thereafter. The present invention will now be explained with the help of examples. EXAMPLES Melamine in the form of powder of molecular weight 126.12 g/mol, PVA in the form of powder of molecular weight 31000 g/mol and Poly(vinyl acetate) (PVAc) in the form of beads of molecular weight 51000 g/mol were used without further treatment. Other reagents used were formaldehyde aqueous (37% w/v) solution, acrylic acid, and sodium hydroxide. All the materials have been stored in the polymer laboratory in closed containers or bags to ensure that the conditions were kept constant throughout the period. The Fourier transform IR spectra (FT-IR) were recorded with a Perkin Elmer IR spectrophotometer (model 8300) in the wave number range of 400 and 4000cm"1 and with samples as KBr pellet. This instrument is available with the DIAT. DSC analysis was carried out with a TA Instruments DSC Q100 V9.8 Build 296 Module. TGA analysis was carried out by instrument Auto TGA 2950HR V5.4 A, Module TGA 1000_C. Unconfined compressive strength (UCS) were measured by Hounsfield - 50Ks, capacity 50 KN universal testing machine at NMRL. The fly ash powder used had the following physical characteristics namely specific gravity 1.9 - 2.2 g/cm3, specific surface area 2.01 - 2.08 cm2/g, pH 11.9 -13.0 and total carbon content 0.2%. The cement used in the experiment was magnesium oxy chloride cement (OCC) having composition of rnagnesite powder and magnesium chloride. The commercial grade guar gum powder having 3340 Cps viscosity was also used. The viscosity was brought down to 230 Cps by the addition of H2C>2 and Gamma irradiation as per the patented procedure. However the viscosity can be brought down by other known methods as well. The MF resin was synthesized in the laboratory. 126.12 g of (One mole) melamine 37% W/V in excess formalin 243 ml (3 mole HCHO) were mixed at about 30-60° C with the pH being kept at alkaline (9.0-9.5). The composition was kept in a magnetic stirrer and the temperature was continuously monitored. On cooling, the hexamethylol melamine separated out and was then filtered washed with water and dried at temperatures not in excess of 40° C. After the addition of water to the formalin, i.e., 38.5% by weight of formaldehyde in water, the pH was adjusted to 9.0 by adding a 1 M NaOH solution (because the methylolated intermediates of the reaction rapidly condense under acidic conditions) and the melamine was added. As hardener, 10% NH4CI solution was used. The viscosity as measured using a type V1-LA/1-R Viscometer was 200 cP by spindle No. R3 at 21.6°C. Methanol was then added to the resultant dried hexamethylolmelamine under acid conditions until dissolution was complete when the solution was neutralized and then filtered with the excess methanol being removed by vacuum distillation and kept in a dessicator. The resultant pure ether (MF resin) is a crystalline solid, colorless with a melting point temperature of 55° C. This ether has limited solubility in water but dissolves readily in water containing a reactive hydrogen atom and its wide range of solubility and polymer compatibility renders it a very versatile cross-linking agent for many potential surface coating polymers. If no catalysts are used then the curing time is lengthy but by addition of strong acid catalysts such as p-toluene sulfonic acid the cycles was reduced considerably and the product was found water soluble. For fast curing 55 grams each of Thio urea and NaOH were added. The resultant cured products of the polymer MF have good flexibility with a high degree of resistance to alkalis. The alkalinity was confirmed by checking pH value which was more than 9.0. The super absorbent polymer composites [SAPC] was prepared by initially mixing 750 ml of distilled acrylic acid [molecular weight 72.06, specific gravity 1.048] 1:1 ratio with distilled water and stirred in mechanical stirrer. During this process 300 grams of KOH [mol. wt 56.11] was added slowly. The pH was 3.5 initially and after two hours of stirring it was 5.5. The stirring process continued for 5 hours. During this ongoing process 08 grams of APS (Ammoniumpersulphate [(NH^SaOs] having mol.wt of 228.20 was mixed with 50 ml of distilled water and stirred in the magnetic stirrer at the temperature of 45 deg C. APS initiates the cross linking of acrylic acid solution. This APS was dropped gently inside the acrylic acid solution under going mechanical stirring with the help of a column. This process continued for 08 hours. This composition became gel subsequently which could be cut by knife into slices. This (SAP) was added with the sand composition as mentioned in the table 1.3. Preparation of Molds OCC, Guar gum Molds The present studies were conducted on 20 grams of guar gum added in 100 ml of distilled water with 5 grams of NaOH placed in the magnetic stirrer and stirred for 2 hrs. 5 ml of formaldehyde (HCHO 37% solution) was added during the stirring process as cross link agents. The combination started becoming paste form. It was stirred for 8 hours and the paste was added in the sand mixture. The influence of incorporation of MF and Guar gum on compressive strength of the oxychloride cement is studied with the help of standard 3cm3 cubes prepared from the Indian Standard consistency pastes having MF and guar gum in different amounts. These cubes (molds) were tested after curing for 28 days as per standard procedure (Indian Standard Institution 1958). Compositions of guar gum and MF were changed from 1% to 2%. The experimental program was divided into three phases. In the first phase four sets of cubical specimens were made, each containing three samples, in order to be tested for compressive and flexural strength after 7 days of standard curing. MF and OCC Molds Various polymer composite samples were prepared to optimize the design as considering the marine environmental nature. Different compositions were based on three polymers melamine formaldehyde and orthophthalate polyester resin mixed with magnesium oxy chloride cement (OCC), Polyvinyl acetate (PVAc) mixed with sea sand The compositions of these molds are given in table 1.1 and the results of their compressive tests are shown in table 1.2. (Table Removed) Table 1.1: Composition of molds prepared & tested at NMRL Where the above abbreviations stand for the following : MF Melamine Formaldehyde Thermoset Polymer Powder SS Fine Sea Sand PVA Polyvinyl alcohol powder PVAc Polyvinyl acetate granules Polyester Orthophthalate Polyester Resin OCC Magnesium oxy chloride cement with composition: magnesia powder.MgCb solution (Table Removed) Table 1.2: Test report of specimens tested at NMRL Where SAP stand for Super absorbent Polymer Based on Poly(acrylic acid) Hydrogel Second phase test specimen preparation: The previous results suggest increased strength needed for the composite material samples. Based on the preliminary data reported from the earlier experimental, four sets of each five numbers of combination of moulds having guar gum, MF, SAP and PVA as tabulated in table 1.3 were prepared again after analyzing the test results of earlier samples at NMRL, Mumbai and CME (Kirkee). The detailed procedure adopted for second phase moulds namely SAP and PVA preparation is briefed in the succeeding paragraphs. (Table Removed) Table 1.3: Composition of second sets molds OCC, PVA molds: 10 w/v% aqueous solution of PVA was prepared by dissolving PVA in 200 ml distilled water and stirred in a magnetic stirrer at 60 deg C for 06 hours. The viscosity was measured continuously every 02 hours. Table 1.4 shows the changes in viscosity. After two hours of stirring, 02 ml of (1.26 grams of MgCIa 6H2O) and 20 ml of 25% aqueous solution of Glutaraldehyde [mol weight: 100.12] was added to the PVA solution to get the desired cross linking ratio. This mixture was added with sand composition as indicated in table 1.3. (Table Removed) Table 1.4: Viscosity of Poly(vinyl alcohol) Solution Preparation of Guar gum & MF-OCC solution mixture: 1.5 grams each of gamma-irradiated guar gum and H2O2 treated low viscosity guar gum powder were mixed separately with 150 ml and 200 ml distilled water respectively and stirred in a mechanical stirrer.. Change in viscosity was measured after 30 minutes as shown in the table 1.5 (Table Removed) Table 1.5: Viscosity changing pattern of low viscosity grade Guar gum Subsequently 1.5 grams of melamine formaldehyde was mixed with MgCI2 gauging solution while stirring and the viscosity was measured as indicated in tablel.6. (Table Removed) Table 1.6: Viscosity changing pattern after adding MF with MgCIa solution The solution was placed under mechanical stirrer and 30 grams of fly ash was added during the process and the viscosity changes are shown in the table 1.7. (Table Removed) Table 1.7: Viscosity change: after adding fly ash The viscosity changes of the MF-OCC solution in 1 hr are shown in the table 1.8. Finally these solutions were mixed with guar gum and the mixture was poured on sea sand to carry out seepage test. (Table Removed) Table 1.8: Viscosity pattern of MF-OCC solution Third phase mold preparation: 5 sets of specimen sample by changing percentage composition of guar gum and MF were prepared as shown in table 1.9. The compositions of guar gum and MF were changed from 1% (2.5 grams) to 2%.(5 grams) of the OCC and sea sand. (Table Removed) Table 1.9: Composition of Sea sand, Magnesia cement, fly ash, Guar gum & MF molds Thermal Analysis of the PCC Composites: The Differential Scanning Calorimetric DSC and Thermo-gravimetric TG Analysis were recorded individually for the Guar gum and MF. DSC analysis of 1% Guar gum 1% MF composites indicates the characteristics of amorphous polymer of GG/MF, the temperature at 40 deg C above which the composite becomes soft, flexible and rubbery and melting temperature Tm' at 151.23 deg C. The melting endotherm of Guar gum is at 117 deg C. The melting temperature of MF is 115 deg C. But the combined product of 1% GG with 1% MF, the melting temperature is 151 deg C. The endotherm shift to higher temperature is due to available impurity. The shifting phase of melting endotherm from base line towards higher temperature range of 151.23 deg C indicates the combination of both product (GG and MF) to form a new composite with broad melting endotherm combining the amorphous nature of composites of Guar gum and MF. Thermo-gravimetric TG Analysis of the combination having 1% Guar gum and 1% MF shows that the weight loss is very less. 3% weight loss is at 123 deg C and 14% at 425.91 deg C. There is a major weight loss after 640 °C. It shows the higher thermal stability. The decomposition temperature of 1% guar gum and 1% MF is higher than the only guar gum and only MF resin, which confirms the enhancement of thermal stability of the intercalated polymer of guar gum and MF resin. This also shows the cross linking of MF with guar gum, leading to high molecular weight thermosetting polymer composite. FTIR Spectral analysis of the MF and MF-Guar gum Composites: Fourier Transform Infrared (FTIR) analysis of MF, low viscosity and irradiated Guar gum and 1% GG and 1% MF was done. All the FTIR spectra of pure and treated guar gum showed very broad band centered at 3300 cm"1 and 2925 cm"1 showing presence of -OH groups in their structures. The FTIR spectra of irradiated guar gum showed additional peaks centered at 2286 cm"1 and at 2838 cm'1 assigning connected aliphatic aldehyde -CH = O groups, denoting cleavage of - D- mannopyranosyl units of galactomannan. The FT-IR spectra of 1% GG and 1% MF show similar bands, such as those at 3700 - 3000 cm"1 (OH stretching vibration), 2924 and 2893 cm"1 (symmetric and asymmetric CH stretching), 1415 cm"1 (OH bending), and 1200-800 cm"1 (C - O and C - C stretching vibrations of the hexapyranosyl). The bend at 1460 cm"1 is due to C -H deformation of _ CH2 in melamine, MF and guar gum. The bend from 1625 -1560cm"1 is secondary amines _ NH in the melamine. Grouting studies In order to develop spraying MF resin based composite to undertake spraying in the sea shore area a composition having sea sand 227.5 gram, magnesia powder 75 gram, MgCb solution 82 ml (2.4g/ml), MF resin 01 gram were mixed and the viscosity was measured in a Viscometer Type VI-L/VI-R, Make MYR. The initial viscosity was 50 cps. The change in viscosity was continuously measured till its solidification for duration of two to four hours (Table 1.8). Studies were also conducted on pure oxychloride cement curing without sea sand filler using MgC^ gauging solution. Effect of water on the cured magnesia cement-sea sand composite was also analysed. Guar gum & Melamine mixture seepage test: To ascertain depth of seepage the guar gum and melamine formaldehyde composition was prepared. This mixture was poured above 1400 grams of sea sand. The seepage studies were conducted at the laboratory scale to make the mixture suitable for construction of platform. The seepage rate of the aqueous solution of (viscosity 65 to 200 cps) mixture of fly ash 30 gram, magnesia powder 42 gram, MgCI2 37 gram, MF resin 1.4 gram and Guar gum 1.4 gram poured on 1400 gram sea sand kept in a graduated container was 3.32 cm3 /min Compressive strength test The influence of incorporation of MF and Guar gum on compressive strength of the oxychloride cement was studied with the help of standard 03x03x03 cm3 cubes prepared from the Indian Standard consistency pastes having MF and guar gum in different amounts. These cubes (molds) were tested after curing for 28 days as per the standard procedure (Indian Standard Institution 1958). The compressive strengths achieved are shown in table 2.0. (Table Removed) Table 2.0: Compressive Strength: Guar gum composition after 28 days Durability Test To check the deterioration of concrete, four sample specimens each having composition of PVA, SAP, Guargum and SAP with MF were immersed in the 35 g/l NaCI solution for a duration of 3 months and the changes in weight and density were recorded (Table 2.1). The samples were checked every week physically to assess any deterioration. The compositions kept in a seawater solution for 3-6 months did not show any deterioration in the four mould samples. (Table Removed) Table 2.1: Molds Saline Water Immersion Test Results Result The summary of results (Table 2.3) indicates the maximum compressive strength achieved by the various composition moulds. Even though the SAP combination resulted in good strength, it is not considered due to high preparation time and the application in coastal operational areas need quick preparation in a stipulated time. Out of the Guar gum composition, the 1% Guar gum and 1% MF combination is accepted due to the inherent advantages of melamine formaldehyde resin namely wear resistance, wet-strength properties, excellent adhesive performance, tendency to give low formaldehyde emission, tremendous load bearing capacity and suitability for compression molding. The results shown in most cases reflect increase in compressive strength with increase in curing period. In addition the hydroxyl groups (OH) available on the hydrocolloids (example: three hydroxyl groups in one glucose ring of the galactomannan ) from the hydrogen bonding with the inorganic part of the cement / sand / mortar that is OH - Si - OH part, that leads to further curing and strengthening of the mortar cement or the grout. Since 1% Guar gum 1% Melamine formaldehyde shows better miscibility in Differential Scanning Calorimeter (DSC) studies, comparison was done with other blends having different compositions of guar gum and melamine formaldehyde, SAP and PVA. The peak shift in the FTIR curve indicates that partial compatibility between the two polymer blends. The first composite having polyester failed to be considered due to earlier deterioration in sea water. The second and third set of composites having guar gum and MF repeatedly resulted in unsuitability due to poor strength. The first set having 1% Guar gum 1% MF composite is the only one to show an increase in strength and the required suitability for strengthening of sea soil for landing of hovercrafts. Conclusion It had demonstrated that the optimized polymer composite having 1% Guar gum 1% MF composite yielded exceptionally good impact strength as high as two fold improvement over earlier attempts. The curing time and temperature conditions have been optimized to match with surface temperature of coastal areas. The thickness of platform was optimized on the basis of results of compressive strength of Guar gum and melamine formaldehyde composite by Westergaard equation Differential Scanning Calorimeter (DSC) observations show that the composite is having homogeneous polymerization along with sea sand. Thermo Gravimetric Analysis (TGA) reveals that composite start decomposition normally in the temperature range 220- 430 deg C. There is a major weight loss after 640 deg C. It shows enhanced decomposition temperature of the MF- guar gum composite. This confirms enhancement of thermal stability of the intercalated polymer of guar gum and MF resin and. cross linking of MF with guar gum, leading to high molecular weight thermosetting polymer composite. (Table Removed) Table 2.3: Summary: Suitability of Mold Compositions ADVANTAGES 1. The technology used in the present invention is simple. 2. In this invention seawater may be used for making the slurry. 3. MF and guar gum resin blends are completely miscible in the amorphous state which shows thermal stability of cured blend of MF-Guar gum resin in the temperature of 151-350 deg C. 4. Thermo-gravimetric analysis indicates major weight loss in the case of MF resin in the temperature of 220-350 deg C. In the combination having 1% Guar gum and 1% MF the weight loss is very less. Weight loss is 14% at 425.9 deg C. There is a major weight loss after 640 deg C. It shows enhanced decomposition temperature of the MF- guar gum composite. This confirms enhancement of thermal stability of the intercalated polymer of guar gum and MF resin and. cross linking of MF with guar gum, leading to high molecular weight thermosetting polymer composite. 5. In addition the hydroxyl groups (OH) available on the hydrocolloids (example: three hydroxyl groups in one glucose ring of the galactomannan in guar gum) form the hydrogen bonding with the inorganic part of the cement / sand / mortar that is OH - Si - OH part, that leads to further curing and strengthening of the mortar cement or the grout. 6. The present Polymer composite cement is cost effective over the conventional cement concrete. 7. Fly ash has been used to an extent of 20-30 % by reducing Oxy chloride cement. Such an option has other beneficial effects like increased compressive strength and reduced cost. 8. Locally available aggregates and fillers can be used in this technique. 9. The tools and plants required are concrete mixer, road /vibratory roller which are readily available. No special training is required 10. The Polymer composite cement gains good mechanical properties within a short period of 2-3 hours. 11. For further curing of the Melamine-Formaldehyde-Polymer Magnesium Oxychloride Cement Concrete Composite additional water curing is not required. 12. After curing, no cracks are developed on the surface. 13. There is no deteriorating effect of continuous heavy rains for 5-6 months. 14. The present composite is ideally suited to make a rapid landing platform at sea shore and river banks and the platform is not deteriorated by continuous slaps of encroaching water. We Claim: 1. A polymer cement composite for preparing landing platforms comprising: - 1-5% of melamine formaldehyde resin - 1 -2% of guargum - 90-98% of cementitious material 2. The polymer cement composite for preparing landing platforms as claimed in claim 1 wherein melamine formaldehyde resin and guargum are present in a 1:1 ratio. 3. The polymer cement composite for preparing landing platforms as claimed in claim 1 wherein the cementitious material comprises : - 6 - 8% of magnesium oxychloride cement, - 3-5% of fly ash and - Sea sand 4. A process for the preparation of the polymer cement composite for preparing landing platforms comprising i. mixing melamine formaldehyde resin and guargum in the 1:1 ratio including the cementitious material to obtain a homogenous mixture, ii. preparing a slurry of the homogenous mixture in step (i) in water, iii. pouring or spraying the said slurry on ground, iv. drying said slurry. 5. The process for preparation of the polymer cement composite for preparing landing platforms wherein the viscosity of said slurry is 200-500cps. 6. The polymer cement composite for preparing landing platforms substantially as herein described with reference to the foregoing examples. 7. The process for the preparation of the polymer cement composite for preparing landing platforms substantially as herein described with reference to the foregoing examples.

Documents:

930-del-2008-abstract.pdf

930-DEL-2008-Claims-(03-08-2012).pdf

930-del-2008-claims.pdf

930-DEL-2008-Correspondence Others-(03-08-2012).pdf

930-del-2008-correspondence-others.pdf

930-del-2008-description (complete).pdf

930-del-2008-form-1.pdf

930-del-2008-form-18.pdf

930-del-2008-form-2.pdf

930-del-2008-form-3.pdf