CN111187475B

CN111187475B - High-aging-resistance thermoplastic polyolefin waterproof coiled material and preparation method thereof

Info

Publication number: CN111187475B
Application number: CN202010043174.1A
Authority: CN
Inventors: 观姗姗; 杨胜; 王晓莉
Original assignee: China Building Materials Suzhou Waterproofing Research Institute Co ltd
Current assignee: China Building Materials Suzhou Waterproofing Research Institute Co ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2022-08-02
Anticipated expiration: 2040-01-15
Also published as: CN111187475A

Abstract

The invention discloses a high-aging-resistance thermoplastic polyolefin waterproof coiled material and a preparation method thereof, wherein the high-aging-resistance thermoplastic polyolefin waterproof coiled material is prepared from thermoplastic polyolefin particles, the thermoplastic polyolefin particles are prepared by mixing and extruding polyolefin and a processing aid, and the polyolefin is prepared by copolymerization reaction of propylene and octene; the weight percentage content of the propylene in the thermoplastic polyolefin particles is more than 88 percent, the weight percentage content of the octene in the thermoplastic polyolefin particles is less than 5 percent and more than 0.5 percent, and the weight average molecular weight of the polyolefin is 5-30 ten thousand; preparation: weighing the raw materials according to the formula proportion, and mixing and copolymerizing the weighed propylene and the weighed octene to prepare polyolefin; extruding and granulating with a processing aid at the working temperature of 180-210 ℃ to obtain thermoplastic polyolefin particles, and tabletting to obtain a thermoplastic polyolefin waterproof coiled material; the invention can solve the problem of service life of the conventional thermoplastic polyolefin waterproof roll (such as TPO waterproof roll).

Description

High-aging-resistance thermoplastic polyolefin waterproof coiled material and preparation method thereof

Technical Field

The invention belongs to the technical field of waterproof rolls, and particularly relates to a high-aging-resistance thermoplastic polyolefin waterproof roll and a preparation method thereof.

Background

The building waterproof material is an important functional material required by the building industry and other related construction industries, and is concerned with the safety of buildings and structures and the life of people. At present, the varieties of building waterproof material doors in China are basically complete and can meet the requirements of various construction projects, but the difference between the overall technical level and foreign countries still exists, and the differences are highlighted in the aspects of the quality and quality level of products, the matching level of application systems, the comprehensive technical level of construction and the like. With the improvement of environmental protection requirements, the environmental protection pressure borne by asphalt waterproof products is greater and greater, and in addition, the homogenization operation phenomenon is serious, enterprises seek new products and find out the mood of road additionally. Thermoplastic polyolefin waterproof rolls have been rapidly developed since the beginning of the 90 th century in foreign commercial applications. Compared with the traditional asphalt waterproof coiled material, the thermoplastic polymer waterproof coiled material represented by the thermoplastic polyolefin waterproof coiled material has the advantages of no pollution, long service life, recoverability, reflection, energy conservation and the like, and is developed rapidly in European and American countries. In recent years, with the advancement of sustainable development strategy and the popularization of green environmental protection concept in China, people's environmental awareness is gradually improved, and people's demand for building waterproof materials with energy conservation, environmental protection and excellent performance is also increased year by year. Therefore, thermoplastic polyolefin waterproof coiled materials become ideal materials in various waterproof materials. However, the research on thermoplastic polyolefin waterproofing materials is not mature enough to date, and many unsolved problems are faced, of which the life span of thermoplastic polyolefin waterproofing sheets such as TPO waterproofing sheets is an important point. The reason for this is that the TPO waterproof sheet is aged by heat, oxygen and sunlight irradiation during long-term outdoor use, which causes the deterioration of physical and mechanical properties, and thus the waterproof capability is lowered or even the TPO waterproof sheet fails.

Disclosure of Invention

The technical problem to be solved by the invention is to provide an improved thermoplastic polyolefin waterproof roll by adopting a new technical scheme, which can solve the service life problem of the conventional thermoplastic polyolefin waterproof roll (such as TPO waterproof roll).

The invention also provides a preparation method of the thermoplastic polyolefin waterproof roll.

In order to solve the technical problems, the invention adopts a technical scheme as follows:

a thermoplastic polyolefin waterproof coiled material is prepared from thermoplastic polyolefin particles, wherein the thermoplastic polyolefin particles are prepared by mixing and extruding polyolefin and a processing aid, and the polyolefin is prepared by copolymerization of propylene and octene; the mass percentage of the propylene in the thermoplastic polyolefin particles is more than 88 percent, the mass percentage of the octene in the thermoplastic polyolefin particles is less than 5 percent and more than 0.5 percent, and the weight average molecular weight of the polyolefin is 5 to 30 ten thousand.

According to some preferred aspects of the present invention, the content by mass of the propylene in the thermoplastic polyolefin particles is 90% or more by mass.

According to some preferred aspects of the present invention, the content of octene in the thermoplastic polyolefin particles is 5% by mass or less and 1% by mass or more.

According to some preferred aspects of the present invention, the content of octene in the thermoplastic polyolefin particles is 5% by mass or less and 3% by mass or more.

According to some preferred aspects of the invention, the copolymerization is carried out at a pressure of 0.08 to 0.12 MPa. According to a particular aspect of the invention, the copolymerization is carried out at a pressure of 0.1 MPa. Preferably, the pressure is kept constant during the copolymerization reaction.

According to some preferred aspects of the invention, the copolymerization is carried out at a temperature of 38 to 42 ℃. According to a particular aspect of the invention, the copolymerization is carried out at a temperature of 40 ℃.

According to some specific and preferred aspects of the present invention, the copolymerization is carried out in the presence of a catalyst, the catalyst being a ziegler-natta catalyst consisting of triethylaluminum and titanium tetrachloride, the catalyst being added in an amount of 0.1 to 1% by mass of the thermoplastic polyolefin particles.

According to some specific and preferred aspects of the present invention, the processing aid comprises 1 to 5 mass% of the ethylene-vinyl acetate copolymer in the thermoplastic polyolefin particles, on a mass% basis.

According to a particular aspect of the invention, the Ethylene Vinyl Acetate (EVA) copolymer is available from Taiwan plastics, Inc. under the designation 7350M.

According to some specific and preferred aspects of the present invention, the processing aid further comprises a carboxylic acid salt in an amount of 2 to 4% by mass of the thermoplastic polyolefin particles.

According to some specific aspects of the invention, the carboxylic acid salt comprises sodium pyrrolidone carboxylate, available from Condst chemical Co.

The invention provides another technical scheme that: a preparation method of the thermoplastic polyolefin waterproof roll comprises the following steps:

weighing the raw materials according to the formula proportion, mixing and copolymerizing the weighed propylene and the weighed octene, terminating the copolymerization reaction by using acid alcohol after the reaction is finished, washing, filtering and drying to prepare polyolefin; extruding and granulating the prepared polyolefin and the processing aid by a double-screw extruder, wherein the working temperature of the double-screw extruder is 180-210 ℃, preparing thermoplastic polyolefin particles, and pressing the prepared thermoplastic polyolefin particles into the thermoplastic polyolefin waterproof coiled material.

According to some particular aspects of the invention, the acid alcohol may be ethanol or acetic acid.

According to some specific aspects of the invention, the washing is performed with alcohol at 35-45 ℃.

According to some specific aspects of the invention, the drying is carried out in a vacuum drying oven at 45-55 ℃.

Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages:

the inventor of the invention finds that the polyolefin with the weight-average molecular weight of 5-30 ten thousand is prepared by copolymerizing propylene and octene with specific content, propylene occupies an absolutely dominant position, the number of side chains formed by octene in the polyolefin is controlled, and the polyolefin polymer material with high molecular structure regularity and few branched chains is prepared.

Drawings

FIG. 1 is a photograph of the macroscopic change of T-A, T-B and T-C after aging for 1 to 5 weeks;

FIG. 2 is an SEM photograph of samples of T-A, T-B and T-C after being unaged and aged for 3 weeks;

FIG. 3 is an unaged IR spectrum of T-A, T-B and T-C;

FIG. 4 is a one week old IR spectrum of T-A, T-B and T-C;

FIG. 5 is a T-A, T-B and T-C aged two-week IR spectrum;

FIG. 6 is a three week infrared spectrum of T-A, T-B and T-C aged;

FIG. 7 is a four-week infrared spectrum of T-A, T-B and T-C aging;

FIG. 8 is a five week infrared spectrum of T-A, T-B and T-C aging;

FIG. 9 is a graph of the thermogravimetric profile of samples of unaged T-A, T-B and T-C waterproofing membranes in nitrogen;

FIG. 10 is a graph of the thermogravimetric profile of samples of two weeks of aged T-A, T-B and T-C waterproofing membranes in nitrogen;

FIG. 11 is a graph of the thermal weight loss in nitrogen for samples of T-A, T-B and T-C waterproofing membranes aged for four weeks.

Detailed Description

The above-described scheme is further illustrated below with reference to specific examples; it is to be understood that these embodiments are provided to illustrate the general principles, essential features and advantages of the present invention, and the present invention is not limited in scope by the following embodiments; the implementation conditions used in the examples can be further adjusted according to specific requirements, and the implementation conditions not indicated are generally the conditions in routine experiments.

In the following, all starting materials are either commercially available or prepared by conventional methods in the art, unless otherwise specified. Ethylene Vinyl Acetate (EVA) was purchased from Taiwan plastics Inc. under the designation 7350M; Ziegler-Natta catalysts are available from North chemical research institute; sodium pyrrolidone carboxylate, available from compands chemical co; propylene and octene were purchased separately from Zhejiang satellite petrochemicals.

Examples

The following examples provide a thermoplastic polyolefin waterproofing membrane made of thermoplastic polyolefin particles, the thermoplastic polyolefin particles are made by mixing and extruding polyolefin and processing aid, the polyolefin is made by copolymerization of propylene and octene; the mass percentage of the propylene in the thermoplastic polyolefin particles is more than 88 percent, the mass percentage of the octene in the thermoplastic polyolefin particles is less than 5 percent and more than 0.5 percent, and the weight average molecular weight of the polyolefin is 5 to 30 ten thousand. In the following embodiments, propylene and octene with specific content are copolymerized to prepare polyolefin with weight average molecular weight of 5-30 ten thousand, propylene occupies an absolute dominant position, the number of side chains formed by octene in polyolefin is controlled, and a high polymer material with high molecular structure regularity and less branched chains is prepared.

Examples 1 to 4

The embodiments provide a thermoplastic polyolefin waterproof coiled material, which is prepared from thermoplastic polyolefin particles, wherein the thermoplastic polyolefin particles are prepared by mixing and extruding polyolefin and a processing aid, and the polyolefin is prepared by copolymerization of propylene and octene; the raw material components and the amounts used in the examples are shown in table 1.

TABLE 1

	Example 1	Example 2	Example 3	Example 4
					Propylene (%)	90	90.5	91	92
Octene (%)	5	4	4.5	4
					EVA(％)	1.5	2.5	2	1.5
Pyrrolidone carboxylic acid sodium (%)	3.0	2.5	2	2
					Ziegler-Natta catalyst (%)	0.5	0.5	0.5	0.5

The preparation method comprises the following steps: weighing the raw materials according to a formula ratio, mixing the weighed propylene and octene, adding a Ziegler-Natta catalyst to initiate polymerization, copolymerizing at a constant pressure of 0.1MPa and at a temperature of 40 ℃, terminating the copolymerization with ethanol after the reaction is finished, washing for 3 times in ethanol at a temperature of 40 ℃, filtering, and drying for 12 hours in a vacuum drying oven at a temperature of 50 ℃ to prepare polyolefin; extruding and granulating the prepared polyolefin, EVA and sodium pyrrolidone carboxylate by a double-screw extruder, wherein the working temperature of the double-screw extruder is 200 +/-5 ℃ to prepare thermoplastic polyolefin particles, and then pressing the prepared thermoplastic polyolefin particles into the thermoplastic polyolefin waterproof roll.

Comparative example

It is essentially the same as example 1, except that: 82% of propylene, 10% of octene, 5% of EVA, 2.5% of carboxylate and 0.5% of Ziegler-Natta catalyst.

Performance testing

The waterproofing membranes prepared in the above-mentioned mutexamples 1 to 2 and comparative mutexample were abbreviated as T-A (corresponding to mutexample 1), T-B (corresponding to mutexample 2) and T-C (corresponding to comparative mutexample), respectively, and the following performance tests were conducted, respectively: 1. the temperature control and the thermal oxidation aging condition during the time control are realized by adopting an air blast drying oven; 2. adopting a scanning electron microscope; 3. a Fourier transform infrared spectrometer; 4. and (5) performing thermogravimetric analyzer characterization.

1. Thermal oxidation aging condition for realizing temperature control and time control by adopting air blowing drying box

The waterproof coiled material is placed in a forced air drying box, the temperature is set to be 135 ℃, and the observation period is 7 days. The whole thermal-oxidative aging process has 5 cycles, x represents the aging cycle, (x ═ 1, 2, 3, 4, 5), and the test results are shown in fig. 1, and it can be clearly observed from fig. 1 that all samples are yellowed in appearance color to different degrees along with the aging time. In the field of polymer synthetic materials, the yellow index is an important index for evaluating the quality and the aging degree of the material. In general, all samples showed a tendency to increase in yellow with time, which was different from T-A, T-B in the rate and extent of yellowing, which was much slower than that of T-C.

2. Using a Scanning Electron Microscope (SEM)

Cutting the waterproof coiled material sample into slender small sections, and then brittle-breaking the sample at low temperature by using liquid nitrogen; adhering the broken surface of the sample to a small table covered with conductive adhesive, fixing the sample on the small metal table by using the conductive adhesive, and performing gold spraying treatment; finally, observing the obtained section by using a scanning electron microscope, wherein the test result is shown in figure 2, and as can be seen from figure 2, after the sample is aged, on one hand, the original structure of the polymer is damaged, so that the surface of the polymer is defective, degradation is caused, and the molecular chain is broken; on the other hand, the small molecule additive in the preparation process of the waterproof coiled material is analyzed and separated out to the surface. Meanwhile, by comparing and analyzing aged SEM images, the T-C aging degree is serious, the silver streaks appear on the surface of the sample, and the T-A, T-B is relatively good.

3. Fourier transform infrared spectrometer

Cutting the dried and clean waterproof coiled material into small pieces of 1cm multiplied by 1cm by using scissors, and numbering different test samples; the test range adopted by the experiment is 4000cm ^-1 To 600cm ^-1 (ii) a Collecting and collating experimental data after the test is finished, and drawing an infrared analysis spectrogram by using software such as Origin and the like, and particularly referring to figures 3-8; wherein FIG. 3 is an unaged IR spectrum of a different waterproofing membrane; FIG. 4 is an infrared spectrum of different waterproof rolls after aging for one week; FIG. 5 is a two-week infrared spectrum of different waterproof rolls; FIG. 6 is an infrared spectrum of three weeks of aging of different waterproof rolls; FIG. 7 is a graph of the four-week infrared spectra of different water-resistant rolls; FIG. 8 is an infrared spectrum of five weeks of aging of various waterproofing membranes; the infrared spectrogram illustrates that the main chain bond is broken along with the aging process, and the aging resistance of T-C is found to be poorer and the aging resistance of T-A and T-B is better than that of T-C by comparison.

4. Thermogravimetric analyzer characterization

Weighing a proper amount of sample to be tested, placing the sample on a balance of a thermal weight loss analyzer, and carrying out an experiment under the protection of nitrogen; the temperature is raised from room temperature to 600 ℃, and the heating rate is 10 ℃/min. So as to obtain a change curve of the residual mass of the sample along with the temperature, and obtaining a change curve of the mass loss rate along with the temperature by derivation, wherein the specific result is shown in fig. 9-11, and fig. 9 is a thermal weight loss curve of an unaged waterproof coiled material sample in nitrogen; FIG. 10 is a graph of the thermal weight loss of samples of aged two-week waterproofing membranes in nitrogen; FIG. 11 is a graph of the thermal weight loss of a sample of an aged four-sided waterproofing membrane in nitrogen; as can be seen from FIGS. 9-11, the aging performance of T-C is poor, and the molecular chain is severely degraded and yellowed in a short time. In contrast, neither T-A nor T-B developed yellowing until 2 weeks of aging, and T-A and T-B were thermally stable and therefore did not show significant changes in the TG curve. With the aging time, all samples were very severely aged after four weeks of aging, at which time severe yellowing of all samples occurred, the TG curves remained consistent again and the thermal decomposition temperature decreased.

According to the different macroscopic tests and microscopic analyses, the polyolefin with the weight-average molecular weight of 5-30 ten thousand is prepared by copolymerizing propylene and octene with specific content, propylene occupies an absolutely dominant position, the number of side chains formed by octene in the polyolefin is controlled, and the high polymer material with high molecular structure regularity and few branched chains is prepared.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the content of the present invention and implement the invention, and not to limit the scope of the invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the scope of the present invention.

Claims

1. A thermoplastic polyolefin waterproof roll material, which is made of thermoplastic polyolefin particles, wherein the thermoplastic polyolefin particles are made by mixing and extruding polyolefin and processing aid, and is characterized in that the polyolefin is made by copolymerization reaction of propylene and octene, the copolymerization reaction is carried out in the presence of a catalyst, the catalyst is a Ziegler-Natta catalyst composed of triethyl aluminum and titanium tetrachloride, and the copolymerization reaction is carried out at the temperature of 38-42 ℃;

the addition amount of the catalyst accounts for 0.1-1% of the thermoplastic polyolefin particles in terms of mass percentage, the mass percentage of the propylene in the thermoplastic polyolefin particles is more than 88%, and the mass percentage of the octene in the thermoplastic polyolefin particles is less than 5% and more than 0.5%;

the processing aid comprises 1-5% by mass of ethylene-vinyl acetate copolymer and 2-4% by mass of carboxylate of the thermoplastic polyolefin particles;

the weight average molecular weight of the polyolefin is 5-30 ten thousand.

2. The thermoplastic polyolefin waterproofing membrane according to claim 1, wherein the mass percentage of propylene in the thermoplastic polyolefin particles is 90% or more.

3. The thermoplastic polyolefin waterproofing membrane according to claim 1 or 2, wherein the content of octene in the thermoplastic polyolefin particles is 5% by mass or less and 1% by mass or more.

4. The thermoplastic polyolefin waterproofing membrane according to claim 3, wherein the content of octene in the thermoplastic polyolefin particles is 5% by mass or less and 3% by mass or more.

5. The thermoplastic polyolefin waterproofing membrane according to claim 1, wherein the copolymerization reaction is carried out under a pressure of 0.08 to 0.12 MPa.

6. The roll of thermoplastic polyolefin waterproofing according to claim 1, characterized in that said carboxylate is sodium pyrrolidone carboxylate.

7. A method for preparing thermoplastic polyolefin waterproof coiled material according to any one of claims 1 to 6, wherein the preparation method comprises the following steps: