Modified titanium dioxide, preparation method of modified titanium dioxide, composition for thermoplastic polyolefin waterproof coiled material, thermoplastic polyolefin waterproof coiled material and preparation method of thermoplastic polyolefin waterproof coiled material

Abstract

The invention relates to the technical field of TPO waterproof coiled materials, and discloses modified titanium dioxide and a preparation method thereof, a composition for a thermoplastic polyolefin waterproof coiled material, the thermoplastic polyolefin waterproof coiled material and a preparation method of the thermoplastic polyolefin waterproof coiled material. The method for preparing the modified titanium dioxide comprises the following steps: in the presence of a solvent, carrying out first heating treatment on titanium dioxide and lignosulfonic acid to obtain an intermediate I; in the presence of an organic solvent, carrying out second heating treatment on the intermediate I and the component I to obtain modified titanium dioxide; the component I is selected from at least one of 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyl benzophenone and 2, 2-dihydroxy-4-methoxybenzophenone, and the component II is selected from at least one of 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyl benzophenone and 2, 2-dihydroxy-4-methoxybenzophenone. The modified titanium dioxide prepared by the method can be applied to the field of TPO waterproof coiled materials. The TPO waterproof coiled material prepared by adopting the composition for the TPO waterproof coiled material disclosed by the invention has excellent anti-aging performance.

Description

Technical Field

[0001] The invention relates to the technical field of thermoplastic polyolefin waterproof coiled materials, and in particular to modified titanium dioxide and a preparation method thereof, a composition for thermoplastic polyolefin waterproof coiled materials, a thermoplastic polyolefin waterproof coiled material and a preparation method thereof. Background Art

[0002] Thermoplastic polyolefin (TPO) is a copolymer formed with ethylene and propylene as the main materials. Because its molecular chain is saturated, the content of tertiary carbon atoms is relatively small, and it does not contain polar atoms, it has a certain chemical stability.

[0003] In addition, TPO material has the advantages of low density and good low-temperature toughness. It also has the good processing performance of plastics and the excellent toughness of rubber, and can be processed using conventional equipment.

[0004] The above excellent properties make its TPO material widely concerned in the field of waterproof membrane.

[0005] However, with the continuous development of the market in recent years and the implementation of "GB 55030-2022", higher requirements have been put forward on many indicators of waterproof membranes, such as requiring waterproof membranes to have excellent durability.

[0006] However, for TPO waterproofing membranes used in exposed single-layer roof waterproofing systems, since they need to be exposed to sunlight for a long time during use, coupled with the increasing light pollution in today's society, this is a severe test for the light stability of TPO waterproofing membranes. In order to better ensure the durability of the waterproof function, it is generally necessary to add light stabilizers to the TPO formula to better improve the product's anti-light aging performance.

[0007] Currently, light stabilizers in TPO formulations include light shielding agents (such as pigments and masterbatches), light stabilizers and auxiliary light stabilizers.

[0008] However, TPO formulas usually also contain flame retardants, antioxidants, plasticizers and other functional additives. The interaction between different components will result in the current light stabilizer modification not achieving the ideal effect. The anti-light aging performance of TPO waterproof membranes obtained by existing technologies still needs to be improved.

[0009] Therefore, it is of great significance to develop a TPO waterproof membrane with good anti-light aging performance. Summary of the invention

[0010] The purpose of the present invention is to overcome the problem of insufficient light aging resistance of TPO waterproofing membrane in the prior art.

[0011] In order to achieve the above object, the first aspect of the present invention provides a method for preparing modified titanium dioxide, the method comprising:

[0012] (1) in the presence of a solvent, subjecting titanium dioxide and lignin sulfonic acid to a first heating treatment to obtain an intermediate I;

[0013] (2) in the presence of an organic solvent, subjecting the intermediate I and component I to a second heating treatment to obtain modified titanium dioxide;

[0014] The component I is selected from at least one of 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octylbenzophenone and 2,2-dihydroxy-4-methoxybenzophenone;

[0015] In step (1), the mass ratio of the titanium dioxide to the lignin sulfonic acid is 1:0.1-0.5. The second aspect of the present invention provides modified titanium dioxide prepared by the method described in the first aspect.

[0016] The third aspect of the present invention provides a composition for thermoplastic polyolefin waterproofing membrane, the composition contains a main agent and an auxiliary agent, the main agent includes a TPO elastomer, component A, component B, and modified titanium dioxide;

[0017] Relative to 100 parts by weight of the TPO elastomer, the content of component A is 5-10 parts by weight, the content of component B is 5-10 parts by weight, and the content of modified titanium dioxide is 2-10 parts by weight;

[0018] The component A is polyethylene and / or polypropylene, and the component B is POE elastomer.

[0019] The modified titanium dioxide is the modified titanium dioxide described in the second aspect above.

[0020] A fourth aspect of the present invention provides a method for preparing a thermoplastic polyolefin waterproof membrane, the method comprising:

[0021] (a) stirring and mixing the components in the composition of the third aspect to obtain a mixture;

[0022] (b) Extruding the mixture to obtain the thermoplastic polyolefin waterproof membrane.

[0023] The fifth aspect of the present invention provides a thermoplastic polyolefin waterproof membrane prepared by the method described in the fourth aspect.

[0024] The method for preparing modified titanium dioxide provided by the present invention is simple and has strong operability. The prepared modified titanium dioxide can be applied to the field of waterproof coiled materials and has a significant advantage in improving the anti-light aging performance of the coiled materials.

[0025] The thermoplastic polyolefin waterproof roll material prepared by using the composition for thermoplastic polyolefin waterproof roll material provided by the invention has excellent light aging resistance, stability and welding performance. DETAILED DESCRIPTION

[0026] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0027] As mentioned above, the first aspect of the present invention provides a method for preparing modified titanium dioxide, the method comprising:

[0028] (1) in the presence of a solvent, subjecting titanium dioxide and lignin sulfonic acid to a first heating treatment to obtain an intermediate I;

[0029] (2) in the presence of an organic solvent, subjecting the intermediate I and component I to a second heating treatment to obtain modified titanium dioxide;

[0030] The component I is selected from at least one of 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octylbenzophenone and 2,2-dihydroxy-4-methoxybenzophenone;

[0031] In step (1), the mass ratio of the titanium dioxide to the lignin sulfonic acid is 1:0.1-0.5.

[0032] Preferably, the conditions of the first heating treatment include: temperature of 110-150°C and time of 2-4h;

[0033] Preferably, the conditions of the second heating treatment include: temperature of 110-150°C, time of 1-3h, and rotation speed of 800-1200rpm. The inventors of the present invention have found that in this preferred case, the obtained modified titanium dioxide is used in the preparation of thermoplastic polyolefin waterproofing membrane, so that the obtained thermoplastic polyolefin waterproofing membrane has better light aging resistance.

[0034] Preferably, in step (1), the amount of the solvent used is 100-150 mL for every 10 g of the titanium dioxide. Preferably, in step (1), the solvent is water.

[0035] The present invention has no particular requirement on the type of water, and those skilled in the art can select it as needed. Exemplarily, the water is deionized water.

[0036] Preferably, in step (2), the mass ratio of the intermediate I to the component I is 1:0.1-0.4. The inventors of the present invention have found that in this preferred case, the obtained modified titanium dioxide is used in the preparation of thermoplastic polyolefin waterproofing membrane, so that the obtained thermoplastic polyolefin waterproofing membrane has better light aging resistance.

[0037] Preferably, in step (2), the amount of the organic solvent used is 80-120 mL per 10 g of the intermediate I.

[0038] Preferably, in step (2), the organic solvent is chloroform.

[0039] According to a preferred specific embodiment, the method further comprises, in step (1), firstly ultrasonically dispersing titanium dioxide and lignin sulfonic acid I, and sequentially subjecting the material obtained by ultrasonic dispersion I to a first heating treatment, a first cooling, a first centrifugation and a first drying treatment to obtain the intermediate I.

[0040] Preferably, the conditions of the first drying treatment include: a temperature of 80-100° C. and a time of 1-3 h.

[0041] Preferably, the method further comprises: in step (2), subjecting the intermediate I and component I to ultrasonic dispersion II, and subjecting the material obtained by ultrasonic dispersion II to a second heating treatment, a second cooling, a second centrifugation and a second drying treatment in sequence to obtain the modified titanium dioxide.

[0042] Preferably, the conditions of the second drying treatment include: temperature of 50-70° C. and time of 1-4 h.

[0043] The present invention has no special requirements for the conditions of the ultrasonic dispersion I and the ultrasonic dispersion II, and those skilled in the art can select them as needed. Exemplarily, the conditions of the ultrasonic dispersion I and the ultrasonic dispersion II each independently include: a time of 20-40 minutes.

[0044] The present invention has no special requirements for the first cooling and the second cooling methods, and those skilled in the art can select them as needed.

[0045] Preferably, the conditions of the first centrifugation and the second centrifugation each independently include: a rotation speed of 8000-10000 rpm and a time of 10-30 min.

[0046] Preferably, the first centrifugation and the second centrifugation are both performed in a high-speed centrifuge.

[0047] According to a preferred embodiment, in step (1), the titanium dioxide is hydroxylated titanium dioxide obtained by hydroxylation treatment.

[0048] Preferably, the hydroxylation treatment comprises the following steps:

[0049] (i) subjecting titanium dioxide, water and concentrated hydrochloric acid to ultrasonic treatment and magnetic stirring in sequence to obtain a mixture;

[0050] (ii) subjecting the mixture to solid-liquid separation to obtain intermediate I;

[0051] (iii) subjecting the intermediate I to a drying treatment I to obtain hydroxylated titanium dioxide.

[0052] It should be noted that, in the present invention, the mass fraction of the concentrated hydrochloric acid is 36wt%-38wt%.

[0053] Preferably, in step (i), the amount of water used is 8-12 mL per 1 g of raw titanium dioxide.

[0054] Preferably, in step (i), the amount of concentrated hydrochloric acid used is 0.4-1 mL per 1 g of raw titanium dioxide.

[0055] Preferably, in step (i), the conditions of the ultrasonic treatment include: temperature of 30-45°C and time of 10-20 min.

[0056] Preferably, in step (i), the conditions for magnetic stirring include: temperature of 30-45° C., rotation speed of 600-1000 rpm, and time of 1-3 h.

[0057] Preferably, in step (iii), the conditions of the drying treatment I include: temperature of -20 to -10°C, vacuum degree of 100Pa-1000Pa, and time of 1-3h.

[0058] According to another preferred embodiment, in step (1), the lignin sulfonic acid is obtained by acidification with a cationic resin.

[0059] Preferably, the acidification comprises the following steps:

[0060] S1: dripping a sodium lignin sulfonate solution with a mass fraction of 20wt%-40wt% into a filter column filled with a sulfonic acid type cation exchange resin for acidification, and collecting the acidified product from the bottom of the filter column;

[0061] S2: The acidified product is subjected to rotary evaporation concentration and drying treatment II in sequence to obtain lignin sulfonic acid.

[0062] Preferably, in step S1, the amount of the sulfonic acid type cation exchange resin used is 1-2 g per 1 mL of the sodium lignin sulfonate solution.

[0063] Preferably, the acidification treatment time is controlled within 1-3 hours.

[0064] The present invention has no special requirements on the conditions of the drying treatment II, and it is only necessary to make the product after rotary evaporation completely dry. Those skilled in the art can select the conditions according to needs.

[0065] As mentioned above, the second aspect of the present invention provides modified titanium dioxide prepared by the method described in the first aspect.

[0066] Preferably, the particle size D50 of the modified titanium dioxide is 50-100 nm.

[0067] It should be noted that the particle size D50 in the present invention refers to the particle size corresponding to when the cumulative distribution reaches 50% in the particle size distribution curve of the modified titanium dioxide.

[0068] As mentioned above, the third aspect of the present invention provides a composition for thermoplastic polyolefin waterproofing membrane, the composition contains a main agent and an auxiliary agent, the main agent includes TPO elastomer, component A, component B, and modified titanium dioxide;

[0069] Relative to 100 parts by weight of the TPO elastomer, the content of component A is 5-10 parts by weight, the content of component B is 5-10 parts by weight, and the content of modified titanium dioxide is 2-10 parts by weight;

[0070] The component A is polyethylene and / or polypropylene, and the component B is POE elastomer;

[0071] The modified titanium dioxide is the modified titanium dioxide described in the second aspect above.

[0072] The inventors of the present invention have found that when the contents of the various components in the composition for thermoplastic polyolefin waterproof membrane are within the above-defined range, the obtained thermoplastic polyolefin waterproof membrane can have both excellent stability and welding performance.

[0073] Preferably, the polyethylene has a melt index of 0.1-2.5 g / 10 min at 190° C. and a load of 2.16 kg, and the polypropylene has a melt index of 1.5-13 g / 10 min at 230° C. and a load of 2.16 kg.

[0074] Preferably, the density of component B is 0.85-0.9 g / cm 3, and the melt index of component B is 1-10 g / 10 min at 230° C. and 2.16 kg load.

[0075] Preferably, the additives include fillers, antioxidants and masterbatches; relative to 100 parts by weight of the TPO elastomer, the content of the filler is 2-20 parts by weight, the content of the antioxidant is 0.1-1 parts by weight, and the content of the masterbatch is 1-5 parts by weight.

[0076] Preferably, the TPO elastomer has a melt mass flow rate of 0.5-15 g / 10 min at 230° C. and under a load of 2.16 kg.

[0077] Preferably, the polyethylene has a density of 0.941-0.960 g / cm 3 High-density polyethylene and / or density not higher than 0.93g / cm 3 of linear low density polyethylene.

[0078] Preferably, the component A is selected from at least one of linear low-density polyethylene (LLDPE), block polypropylene (PPB), random copolymer polypropylene (PPR) and homopolymer polypropylene (PPH).

[0079] Preferably, the component B is selected from at least one of ExxonMobil Vistamaxx 3020, ExxonMobil Vistamaxx 3000 and Dow 2300.

[0080] Preferably, the filler is light calcium carbonate and / or heavy calcium carbonate.

[0081] Preferably, the antioxidant is selected from at least one of antioxidant 1010 , antioxidant 1076 and antioxidant 168 .

[0082] As mentioned above, the fourth aspect of the present invention provides a method for preparing a thermoplastic polyolefin waterproof membrane, the method comprising:

[0083] (a) stirring and mixing the components in the composition of the third aspect to obtain a mixture;

[0084] (b) Extruding the mixture to obtain the thermoplastic polyolefin waterproof membrane.

[0085] Exemplarily, the stirring and mixing can be performed in a high-speed mixer.

[0086] Preferably, in step (a), the stirring and mixing conditions include: temperature of 20-35° C., rotation speed of 300-1000 rpm, and time of 20-40 min.

[0087] Preferably, in step (b), the extrusion molding conditions include: extruder temperature of 145-210° C., screw speed of 10-40 rpm, and line speed of 3-6 m / min.

[0088] Preferably, the method further comprises: calendering, pulling and winding the material obtained by the extrusion molding in sequence.

[0089] The present invention has no special requirements for the conditions of the calendering, the pulling and the winding, and those skilled in the art can select them within the known parameter range in the art as needed.

[0090] As mentioned above, the fifth aspect of the present invention provides a thermoplastic polyolefin waterproof membrane prepared by the method described in the fourth aspect.

[0091] The present invention will be described in detail below by way of examples. In the following examples, unless otherwise specified, the instruments, reagents, materials, etc. involved are all conventional instruments, reagents, materials, etc., which can be obtained through regular commercial channels. Among them, unless otherwise specified, the reagents used are all commercially available analytically pure products.

[0092] Raw material titanium dioxide: purchased from Xuancheng Jingrui New Materials Co., Ltd., brand VK-T50.

[0093] Concentrated hydrochloric acid: mass fraction is 38wt%.

[0094] Sodium lignin sulfonate solution: the mass fraction is 30wt%, wherein the sodium lignin sulfonate is purchased from Sigma-Aldrich Company with the brand number 471038.

[0095] Sulfonic acid cation exchange resin: purchased from Elest (Shanghai) New Material Technology Co., Ltd., with spherical particles in the shape and a particle size range of 0.3-1.25 mm.

[0096] Organic solvent: chloroform.

[0097] Component I:

[0098] Component I-1: 2-Hydroxy-4-methoxybenzophenone, purchased from Merck KGaA, Darmstadt, Germany, with the brand name PHR1074.

[0099] Component I-2: 2-Hydroxy-4-octylbenzophenone, purchased from Nantong Runfeng Petrochemical Co., Ltd., brand name UV531.

[0100] Component I-3: 2,2-dihydroxy-4-methoxybenzophenone, purchased from Shanghai Macklin Biochemical Technology Co., Ltd. (MACKLIN), brand number D806500.

[0101] Component I-D1: hexamethylphosphoric triamide, purchased from Sigma-Aldrich Company, brand number 52730.

[0102] TPO elastomer: the melt mass flow rate under the temperature of 230°C and a load of 2.16 kg is 0.6 g / 10 min. It was purchased from Rodebasel, the Netherlands, with a brand name of CA10A.

[0103] Component A:

[0104] Linear low-density polyethylene: LLDPE, density is 0.919 g / cm 3 , the melt index is 2.1 g / 10 min at 190 ° C and 2.16 kg load, purchased from ExxonMobil, brand name ExxonMobil TM LD 2119.LN Molding.

[0105] Homopolymer polypropylene (PPH), with a melt index of 2.8 g / 10 min at 230 °C and a load of 2.16 kg, was purchased from ExxonMobil Corporation under the brand name ExxonMobil TM PP4712E1.

[0106] Block polypropylene (PPB) with a melt index of 2.5 g / 10 min at 230° C. and a load of 2.16 kg was purchased from Dushanzi Petrochemical Company of PetroChina Co., Ltd. with a brand name of K8003.

[0107] Random copolymer polypropylene (PPR), with a melt index of 12 g / 10 min at 230 °C and a load of 2.16 kg, purchased from ExxonMobil Corporation, with the brand name Exceed TM PP9054.

[0108] Component B:

[0109] Component B-1: Density 0.874 g / cm 3 The melt index is 3 g / 10 min at 230°C and 2.16 kg load. It is purchased from ExxonMobil and has the brand name Vistamaxx 3020.

[0110] Component B-2: density 0.873 g / cm 3 The melt index is 8 g / 10 min at 230°C and 2.16 kg load. It is purchased from ExxonMobil and its brand is Vistamaxx 3000.

[0111] Component B-3: density 0.867 g / cm 3The melt index is 2g / 10min at 230°C and 2.16kg load. It is purchased from Dow Chemical Company of the United States with a brand number of 2300.

[0112] Filler: Heavy calcium carbonate, purchased from Omiya Group, brand OM10.

[0113] Antioxidant: Antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) was purchased from BASF (China) Co., Ltd. with the brand name Irganox1010.

[0114] Masterbatch: White masterbatch, purchased from Jining Wancai Polymer Materials Co., Ltd., brand number 0104.

[0115] The following preparation examples of series A are used to illustrate the preparation of hydroxylated titanium dioxide.

[0116] Preparation Example A1

[0117] (i) titanium dioxide (5 g), water (50 mL of deionized water) and concentrated hydrochloric acid (5 mL) were sequentially subjected to ultrasonic treatment and magnetic stirring to obtain a mixture;

[0118] (ii) subjecting the mixture to solid-liquid separation to obtain intermediate I;

[0119] (iii) subjecting the intermediate I to a drying treatment I to obtain hydroxylated titanium dioxide, named QT1;

[0120] Ultrasonic treatment: temperature 40°C, time 10 min;

[0121] Magnetic stirring: temperature is 30°C, speed is 800 rpm, time is 2 h;

[0122] Drying treatment I: temperature is -15°C, vacuum degree is 500Pa, and time is 2h.

[0123] Preparation Example A2

[0124] This preparation example is carried out by a method similar to that of Preparation Example A1, except that in this preparation example, the amount of raw titanium dioxide used is 10 g, the amount of deionized water used is 80 mL, and the amount of concentrated hydrochloric acid used is 9 mL, and hydroxylated titanium dioxide is prepared, named QT2.

[0125] Preparation Example B

[0126] This preparation example is used to illustrate the preparation of lignin sulfonic acid:

[0127] S1: dripping a 30 wt% sodium lignin sulfonate solution (50 mL) into a filter column filled with a sulfonic acid type cation exchange resin (100 g) for acidification (time controlled within 2 h), and collecting the acidified product from the bottom of the filter column;

[0128] S2: The acidified product is subjected to rotary evaporation concentration and drying treatment II in sequence to obtain lignin sulfonic acid.

[0129] Preparation Example 1

[0130] This preparation example is used to illustrate that the present invention prepares modified titanium dioxide according to the formula and process parameters in Table 1 and the following method.

[0131] (1) In the presence of water (deionized water), firstly subjecting hydroxylated titanium dioxide and lignin sulfonic acid (prepared in the above-mentioned Preparation Example B) to ultrasonic dispersion I, and sequentially subjecting the material obtained by ultrasonic dispersion I to a first heating treatment, a first cooling treatment, a first centrifugation treatment and a first drying treatment to obtain an intermediate I;

[0132] (2) in the presence of an organic solvent, the intermediate I and component I are subjected to ultrasonic dispersion II, and the material obtained by ultrasonic dispersion II is subjected to a second heating treatment, a second cooling, a second centrifugation, and a second drying treatment in sequence to obtain modified titanium dioxide, which is named modified TiO 2 -T1;

[0133] The conditions of ultrasonic dispersion I and ultrasonic dispersion II are: time 30 min;

[0134] The conditions of the first centrifugation and the second centrifugation are: a speed of 8000 rpm and a time of 20 min;

[0135] The conditions of the first drying treatment include: temperature of 80° C. and time of 2 hours.

[0136] The conditions of the second drying treatment include: temperature of 50° C. and time of 3 hours.

[0137] Preparation Examples 2 to 4 were all carried out using a method similar to Preparation Example 1, except that the formulas were different, as shown in Table 1.

[0138] Preparation Example 5

[0139] This preparation example is carried out in a similar manner to that of Preparation Example 1, except that in step (2), the temperature of the second heating treatment is 80° C., and the rest is the same as that of Preparation Example 1;

[0140] The modified titanium dioxide was prepared and named as modified TiO 2 -T5.

[0141] Comparative Preparation Example 1

[0142] In the presence of an organic solvent, 15 g of hydroxylated titanium dioxide QT1 and 4 g of benzophenone-4,4'-dicarboxylic acid were subjected to ultrasonic dispersion I, and the material obtained by the ultrasonic dispersion I was subjected to a first heating treatment (reacting at 120°C for 2 h), a first cooling, a first centrifugation and a first drying treatment in sequence to obtain modified titanium dioxide, which was named modified TiO 2 -DT1;

[0143] The process parameters not listed are the same as those in step (1) of Preparation Example 1.

[0144] Comparative Preparation Example 2

[0145] In the presence of water, 15 g of hydroxylated titanium dioxide QT1 and 6 g of lignin sulfonic acid (prepared in the above-mentioned Preparation Example B) were subjected to ultrasonic dispersion I, and the material obtained by the ultrasonic dispersion I was subjected to a first heating treatment, a first cooling treatment, a first centrifugation treatment and a first drying treatment in sequence to obtain modified titanium dioxide, which was named modified TiO 2 -DT2;

[0146] The process parameters not listed are the same as those in step (1) of Preparation Example 1.

[0147] Comparative Preparation Example 3

[0148] This comparative preparation example is carried out in a similar manner to Preparation Example 1, except that in step (2), this comparative preparation example uses an equal mass of component I-D1 to replace component I-1 in Preparation Example 1, and the rest is the same as Preparation Example 1;

[0149] The modified titanium dioxide was prepared and named as modified TiO 2 -DT3.

[0150] Table 1

[0151]

[0152] Different raw material formulations are used in the following examples of the present invention. The amounts of raw materials are all parts by weight unless otherwise specified, and each part by weight represents 100 g.

[0153] Example 1

[0154] This example is used to illustrate the formulation of the composition for thermoplastic polyolefin waterproof membrane in reference to Table 2, and to prepare the thermoplastic polyolefin waterproof membrane according to the following method.

[0155] (a) stirring and mixing the composition for thermoplastic polyolefin waterproof membrane in a high-speed stirrer to obtain a mixture;

[0156] (b) extruding the mixed material, and then calendering, pulling and winding the material obtained by the extrusion molding in sequence to obtain the thermoplastic polyolefin waterproof membrane;

[0157] The stirring temperature was 25°C, the rotation speed was 800 rpm, and the time was 20 min.

[0158] Unless otherwise specified, Examples 2 to 4 are all carried out using a method similar to that of Example 1, with the differences being the formulations and process parameters, as shown in Table 2.

[0159] Table 2

[0160] Example 1 Example 2 Example 3 Example 4 Main agent TPO elastomer / parts by weight 100 100 100 100 Component A type LLDPE PPB PPR PPH Dosage / weight 10 5 8 Same as Example 1 Component B type Component B-1 Component B-2 Component B-3 Component B-3 Dosage / weight 8 5 10 Same as Example 1 Modified Titanium Dioxide type <![CDATA[Modified TiO 2 -T1]]> <![CDATA[Modified TiO 2 -T2]]> <![CDATA[Modified TiO 2 -T3]]> Same as Example 1 Dosage / weight 6 3 10 Same as Example 1 Additives filler Dosage / weight 15 7 20 Same as Example 1 Antioxidants Dosage / weight 0.5 0.3 1 Same as Example 1 Masterbatch Dosage / weight 2 2 2 Same as Example 1 Extrusion Temperature / ℃ 180 195 210 Same as Example 1 Screw speed / rpm 18 15 25 Same as Example 1 Line speed / (m / min) 3.5 4 4.5 Same as Example 1

[0161] Example 5

[0162] This example is carried out in a similar manner to Example 1, except that this example uses equal weight portions of modified TiO 2 -T4 replaces the modified TiO in Example 1 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0163] Example 6

[0164] This example is carried out in a similar manner to Example 1, except that this example uses equal weight portions of modified TiO 2 -T5 replaces the modified TiO in Example 1 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0165] Comparative Example 1

[0166] This comparative example was carried out in a similar manner to Example 1, except that: this comparative example used equal weight portions of modified TiO 2 -DT1 replaces the modified TiO in Example 1 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0167] Comparative Example 2

[0168] This comparative example was carried out in a similar manner to Example 1, except that: this comparative example used equal weight portions of modified TiO 2 -DT2 replaces the modified TiO in Example 1 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0169] Comparative Example 3

[0170] This comparative example was carried out in a similar manner to Example 1, except that: this comparative example used equal weight portions of modified TiO 2 -DT3 replaces the modified TiO in Example 1 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0171] Comparative Example 4

[0172] This comparative example was carried out in a similar manner to Example 1, except that the modified TiO 2 -T1, and the rest are the same as in Example 1, to prepare a thermoplastic polyolefin waterproof membrane.

[0173] Test Case

[0174] (1) The untreated physical and mechanical properties of the thermoplastic polyolefin waterproof membrane prepared in the above example were tested according to the method specified in Class H of GB 27789-2011. The results are shown in Table 3. Specifically:

[0175] (2) The retention rate of mechanical properties (tensile strength, elongation at break) of thermoplastic polyolefin waterproof membrane after UV treatment for 14 days represents the light aging resistance of thermoplastic polyolefin waterproof membrane;

[0176] Tensile strength retention rate = tensile strength after UV treatment / tensile strength without treatment * 100%;

[0177] Retention rate of elongation at break = retention rate of elongation at break after UV treatment / retention rate of elongation at break without treatment*100%;

[0178] (3) The seam peel strength of the thermoplastic polyolefin waterproof membrane prepared by a manual welding gun (welding temperature is 390-420°C) represents the welding performance of the thermoplastic polyolefin waterproof membrane;

[0179] (4) The temperature corresponding to 5% of the curve obtained by the thermogravimetric test (TG test, the test conditions are air atmosphere, the temperature rise range is from room temperature to 600°C, and the heating rate is 10°C / min) is taken as the corresponding index to measure the thermal stability of different samples.

[0180] Table 3

[0181]

[0182] It can be seen from the above results that the modified titanium dioxide obtained by the method for preparing modified titanium dioxide provided by the present invention has good application prospects in the field of thermoplastic polyolefin waterproof rolls. The thermoplastic polyolefin waterproof roll prepared by the composition for thermoplastic polyolefin waterproof roll provided by the present invention can maintain a good balance in light aging resistance, stability and welding performance.

[0183] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing modified titanium dioxide, characterized in that: The method includes: (1) in the presence of a solvent, subjecting titanium dioxide and lignin sulfonic acid to a first heating treatment to obtain an intermediate I; (2) in the presence of an organic solvent, subjecting the intermediate I and component I to a second heating treatment to obtain modified titanium dioxide; The component I is selected from at least one of 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octylbenzophenone and 2,2-dihydroxy-4-methoxybenzophenone; In step (1), the mass ratio of the titanium dioxide to the lignin sulfonic acid is 1:0.1-0.

5.

2. The method according to claim 1, wherein: The conditions of the first heating treatment include: temperature of 110-150°C and time of 2-4h; And / or, the conditions of the second heating treatment include: temperature of 110-150° C., time of 1-3 h, and rotation speed of 800-1200 rpm.

3. The method according to claim 1 or 2, wherein: In step (2), the mass ratio of the intermediate I to the component I is 1:0.1-0.

4.

4. Modified titanium dioxide prepared by the method described in any one of claims 1 to 3.

5. A composition for thermoplastic polyolefin waterproofing membrane, characterized in that: The composition contains a main agent and an auxiliary agent, wherein the main agent includes a TPO elastomer, component A, component B, and modified titanium dioxide; Relative to 100 parts by weight of the TPO elastomer, the content of component A is 5-10 parts by weight, the content of component B is 5-10 parts by weight, and the content of modified titanium dioxide is 2-10 parts by weight; The component A is polyethylene and / or polypropylene, and the component B is POE elastomer; The modified titanium dioxide is the modified titanium dioxide in claim 4.

6. The composition according to claim 5, wherein The additives include fillers, antioxidants and masterbatches; relative to 100 parts by weight of the TPO elastomer, the content of the filler is 2-20 parts by weight, the content of the antioxidant is 0.1-1 parts by weight, and the content of the masterbatch is 1-5 parts by weight; and / or, the TPO elastomer has a melt mass flow rate of 0.5-15 g / 10 min at 230° C. and under a load of 2.16 kg; And / or, the polyethylene is a high-density polyethylene with a density of 0.941-0.960 g / cm3 and / or a linear low-density polyethylene with a density not higher than 0.93 g / cm3.

7. The composition according to claim 6, wherein The filler is light calcium carbonate and / or heavy calcium carbonate; And / or, the antioxidant is selected from at least one of antioxidant 1010 , antioxidant 1076 and antioxidant 168 .

8. A method for preparing a thermoplastic polyolefin waterproofing membrane, characterized in that: The method includes: (a) stirring and mixing the components in the composition according to any one of claims 5 to 7 to obtain a mixture; (b) Extruding the mixture to obtain the thermoplastic polyolefin waterproof membrane.

9. The method according to claim 8, wherein: In step (a), the stirring and mixing conditions include: temperature of 20-35° C., rotation speed of 300-1000 rpm, and time of 20-40 min; And / or, in step (b), the extrusion molding conditions include: extruder temperature of 145-210° C., screw speed of 10-40 rpm, and line speed of 3-6 m / min.

10. Thermoplastic polyolefin waterproofing membrane prepared by the method according to claim 8 or 9.

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