Displaying publications 1 - 20 of 51 in total

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  1. Aisyah HA, Paridah MT, Sapuan SM, Ilyas RA, Khalina A, Nurazzi NM, et al.
    Polymers (Basel), 2021 Feb 02;13(3).
    PMID: 33540731 DOI: 10.3390/polym13030471
    Over the last decade, the progressive application of natural fibres in polymer composites has had a major effect in alleviating environmental impacts. Recently, there is a growing interest in the development of green materials in a woven form by utilising natural fibres from lignocellulosic materials for many applications such as structural, non-structural composites, household utilities, automobile parts, aerospace components, flooring, and ballistic materials. Woven materials are one of the most promising materials for substituting or hybridising with synthetic polymeric materials in the production of natural fibre polymer composites (NFPCs). These woven materials are flexible, able to be tailored to the specific needs and have better mechanical properties due to their weaving structures. Seeing that the potential advantages of woven materials in the fabrication of NFPC, this paper presents a detailed review of studies related to woven materials. A variety of factors that influence the properties of the resultant woven NFRC such as yarn characteristics, fabric properties as well as manufacturing parameters were discussed. Past and current research efforts on the development of woven NFPCs from various polymer matrices including polypropylene, polylactic acid, epoxy and polyester and the properties of the resultant composites were also compiled. Last but not least, the applications, challenges, and prospects in the field also were highlighted.
  2. Rafiqah SA, Khalina A, Harmaen AS, Tawakkal IA, Zaman K, Asim M, et al.
    Polymers (Basel), 2021 Apr 29;13(9).
    PMID: 33946989 DOI: 10.3390/polym13091436
    Researchers and companies have increasingly been drawn to biodegradable polymers and composites because of their environmental resilience, eco-friendliness, and suitability for a range of applications. For various uses, biodegradable fabrics use biodegradable polymers or natural fibers as reinforcement. Many approaches have been taken to achieve better compatibility for tailored and improved material properties. In this article, PBS (polybutylene succinate) was chosen as the main topic due to its excellent properties and intensive interest among industrial and researchers. PBS is an environmentally safe biopolymer that has some special properties, such as good clarity and processability, a shiny look, and flexibility, but it also has some drawbacks, such as brittleness. PBS-based natural fiber composites are completely biodegradable and have strong physical properties. Several research studies on PBS-based composites have been published, including physical, mechanical, and thermal assessments of the properties and its ability to replace petroleum-based materials, but no systematic analysis of up-to-date research evidence is currently available in the literature. The aim of this analysis is to highlight recent developments in PBS research and production, as well as its natural fiber composites. The current research efforts focus on the synthesis, copolymers and biodegradability for its properties, trends, challenges and prospects in the field of PBS and its composites also reviewed in this paper.
  3. Uma E, Lee CH, Shapiai SNHBM, Binti Mat Nor AN, Soe HHK, Varghese E
    PMID: 33426130 DOI: 10.4103/jehp.jehp_195_20
    BACKGROUND: Undergraduate dental students have to do multiple tasks as part of their extensive curriculum in order to achieve the proficiencies expected of them. During the course of their study, a tendency to procrastinate and question their self-efficacy is detrimental for the students. The aim of this study was to evaluate the level of procrastination and self-efficacy and its related factors among dental undergraduate students.

    SUBJECTS AND METHODS: This cross-sectional study was conducted among all (n = 361) consented dental undergraduate students of our dental school. A twenty-item Lay's Procrastination Scale for student population and a ten-item General Self-Efficacy Scale were used for the study after getting institutional ethical approval. The quantitative data were explained using descriptive statistics. Independent sample t-test and ANOVA were used to determine the association between self-efficacy, academic procrastination, and genders and academic years. Pearson correlation coefficient was used to determine the association between self-efficacy and procrastination. Multiple linear regression analysis was performed to determine the related factors to academic procrastination.

    RESULTS: High procrastination (score ≥62) was seen among 28.5% of students. The mean self-efficacy score was 29.5. There was no significant difference between genders for procrastination scores (P = 0.835) and between academic years (P = 0.226). Males showed significantly more self-efficacy (P < 0.001), and self-efficacy did not show any significant difference (P = 0.204) between academic years though a tendency for year 5 students to have lower self-efficacy scores was observed. Academic procrastination was negatively correlated with self-efficacy (r = -0.238 and P < 0.001).

    CONCLUSIONS: For dental undergraduates who have cognitive load as well as work associated with patients, procrastination and self-efficacy are negatively correlated.

  4. Xie CB, Chan MY, Teo SG, Low AF, Tan HC, Lee CH
    Singapore Med J, 2011 Nov;52(11):835-9.
    PMID: 22173254
    There is a paucity of data on acute myocardial infarction (AMI) in young Asian women and of comparative data among various ethnic groups with respect to risk factor profile and clinical outcomes. We present a comprehensive overview of the clinical characteristics of young Asian women with AMI and a comparative analysis among Chinese, Malay and Indian women in a multi-ethnic Asian country.
  5. Tan H, Mong GR, Wong SL, Wong KY, Sheng DDCV, Nyakuma BB, et al.
    Environ Sci Pollut Res Int, 2024 Jan;31(1):109-126.
    PMID: 38040882 DOI: 10.1007/s11356-023-31228-7
    This paper presents the landscape of research on airborne microplastics and nanoplastics (MPs/NPs) according to the bibliometric analysis of 147 documents issued between 2015 and 2021, extracted from the Web of Science database. The publications on airborne MPs/NPs have increased rapidly from 2015 onwards, which is largely due to the existence of funding support. Science of the Total Environment is one of the prominent journals in publishing related papers. China, England, the USA, and European Countries have produced a significant output of airborne MP/NP research works, which is associated with the availability of funding agencies regionally or nationally. The research hotspot on the topic ranges from the transport of airborne MPs/NPs to their deposition in the terrestrial or aquatic environments, along with the contamination of samples by indoor MPs/NPs. Most of the publications are either research or review papers related to MPs/NPs. It is crucial to share the understanding of global plastic pollution and its unfavorable effects on humankind by promoting awareness of the existence and impact of MPs/NPs. Funding agencies are vital in boosting the research development of airborne MPs/NPs. Some countries that are lacking funding support were able to publish research findings related to the field of interest, however, with lesser research output. Without sufficient fundings, some impactful publications may not be able to carry a substantial impact in sharing the findings and discoveries with the mass public.
  6. Lee CH, Ngeow YF
    Med J Malaysia, 1983 Mar;38(1):23-6.
    PMID: 6633329
    Genital discharge from patients unth. smear positive gonorrhoea was transported from the clinic to the laboratory in. Stuart's transport medium (Oxoid CM 111). Within. six hours of transit time the recovery rate of gonococci was 94%. When compared with "bedside" inoculation onto Modified Thayer Martin medium, there was no significant difference in recovery rates up to 6 hours of transportation in Stuart's transport medium, However, the rate of isolation of gonococci was significantly reduced after 20 to 30 hours of transportation. It is concluded that Stuart's transport medium is an acceptable transport medium for specimens containing gonococci when specimens reach the laboratory within 6 hours of collection.
  7. Shukor MY, Rahman MF, Shamaan NA, Lee CH, Karim MI, Syed MA
    Appl Biochem Biotechnol, 2008 Mar;144(3):293-300.
    PMID: 18556818
    Molybdenum-reducing activity in the heterotrophic bacteria is a phenomenon that has been reported for more than 100 years. In the presence of molybdenum in the growth media, bacterial colonies turn to blue. The enzyme(s) responsible for the reduction of molybdenum to molybdenum blue in these bacteria has never been purified. In our quest to purify the molybdenum-reducing enzyme, we have devised a better substrate for the enzyme activity using laboratory-prepared phosphomolybdate instead of the commercial 12-phosphomolybdate we developed previously. Using laboratory-prepared phosphomolybdate, the highest activity is given by 10:4-phosphomolybdate. The apparent Michaelis constant, Km for the laboratory-prepared 10:4-phosphomolybdate is 2.56 +/- 0.25 mM (arbitrary concentration), whereas the apparent V(max) is 99.4 +/- 2.85 nmol Mo-blue min(-1) mg(-1) protein. The apparent Michaelis constant or Km for NADH as the electron donor is 1.38 +/- 0.09 mM, whereas the apparent V(max) is 102.6 +/- 1.73 nmol Mo-blue min(-1) mg(-l) protein. The apparent Km and V(max) for another electron donor, NADPH, is 1.43 +/- 0.10 mM and 57.16 +/- 1.01 nmol Mo-blue min(-1) mg(-1) protein, respectively, using the same batch of molybdenum-reducing enzyme. The apparent V(max) obtained for NADH and 10:4-phosphomolybdate is approximately 13 times better than 12-phoshomolybdate using the same batch of enzyme, and hence, the laboratory-prepared phosphomolybdate is a much better substrate than 12-phoshomolybdate. In addition, 10:4-phosphomolybdate can be routinely prepared from phosphate and molybdate, two common chemicals in the laboratory.
  8. Grismer LL, Wood PL, Lee CH, Quah ES, Anuar S, Ngadi E, et al.
    Zootaxa, 2015 Apr 20;3948(1):1-23.
    PMID: 25947760 DOI: 10.11646/zootaxa.3948.1.1
    An integrative taxonomic analysis is used to identify and describe two new species of the agamid genus Bronchocela (Kuhl) from Peninsular Malaysia: an upland species B. shenlong sp. nov. from Bukit Larut, Perak in the Bintang Mountain Range and Parit Falls, Cameron Highlands, Pahang in the Titiwangsa Mountain Range and an insular species, B. rayaensis sp. nov., from Pulau Langkawi, Kedah off the northwest coast on the border with Thailand. Both species are diagnosed from each other and all other species of Bronchocela on the basis of body shape, scale morphology, and color pattern. The analysis also demonstrates the remarkable genetic similarity of B. cristatella (Kuhl) throughout 1120 km of its range from northern Peninsular Malaysia to western Borneo despite its highly variable coloration and pattern. The two new species are appended to a rapidly growing list of newly described lizard species (60 to date) from Peninsular Malaysia tallied within the last decade.
  9. Lee CH, Ko AM, Yang FM, Hung CC, Warnakulasuriya S, Ibrahim SO, et al.
    JAMA Psychiatry, 2018 03 01;75(3):261-269.
    PMID: 29417149 DOI: 10.1001/jamapsychiatry.2017.4307
    Importance: Betel-quid (BQ) is the fourth most popular psychoactive agent worldwide. An emerging trend across Asia is the addictive consumption of BQ, which is associated with oral cancer and other health consequences.

    Objective: To investigate the validity and pattern of DSM-5-defined BQ use disorder (BUD) and its association with oral potentially malignant disorder (OPMD) among Asian populations.

    Design, Setting, and Participants: In-person interviews were conducted from January 1, 2009, to February 28, 2010, among a random sample of 8922 noninstitutionalized adults from the Asian Betel-quid Consortium study, an Asian representative survey of 6 BQ-endemic populations. Statistical analysis was performed from January 1, 2015, to December 31, 2016.

    Main Outcomes and Measures: Participants were evaluated for BUD using DSM-5 criteria for substance use disorder and for OPMD using a clinical oral examination. Current users of BQ with 0 to 1 symptoms were classified as having no BUD, those with 2 to 3 symptoms as having mild BUD, those with 4 to 5 symptoms as having moderate BUD, and those with 6 or more symptoms as having severe BUD.

    Results: Among the 8922 participants (4564 women and 4358 men; mean [SD] age, 44.2 [0.2] years), DSM-5 symptoms showed sufficient unidimensionality to act as a valid measure for BUD. The 12-month prevalence of DSM-5-defined BUD in the 6 study populations was 18.0% (mild BUD, 3.2%; moderate BUD, 4.3%; and severe BUD, 10.5%). The 12-month proportion of DSM-5-defined BUD among current users of BQ was 86.0% (mild BUD, 15.5%; moderate BUD, 20.6%; and severe BUD, 50.0%). Sex, age, low educational level, smoking, and drinking were significantly associated with BUD. Among individuals who used BQ, family use, high frequency of use, and amount of BQ used were significantly linked to moderate to severe BUD. Compared with individuals who did not use BQ, those who used BQ and had no BUD showed a 22.0-fold (95% CI, 4.3-112.4) risk of OPMD (P 

  10. Lee CH, Ko AM, Yen CF, Chu KS, Gao YJ, Warnakulasuriya S, et al.
    Br J Psychiatry, 2012 Nov;201(5):383-91.
    PMID: 22995631 DOI: 10.1192/bjp.bp.111.107961
    Despite gradual understanding of the multidimensional health consequences of betel-quid chewing, information on the effects of dependent use is scant.
  11. Lee CH, Chiang SL, Ko AM, Hua CH, Tsai MH, Warnakulasuriya S, et al.
    Addiction, 2014 Jul;109(7):1194-204.
    PMID: 24650227 DOI: 10.1111/add.12530
    Betel-quid (BQ) contains biologically psychoactive ingredients; however, data are limited concerning the symptoms and syndrome of BQ dependence among chewers. The aims of this study were to evaluate the ingredients-associated BQ dependence syndrome and country-specific chewing features and behaviour for BQ dependence among chewers from six Asian communities.
  12. Chan MY, Tan K, Tan HC, Huan PT, Li B, Phua QH, et al.
    Pharmacogenomics, 2012 Apr;13(5):533-42.
    PMID: 22462746 DOI: 10.2217/pgs.12.24
    AIM, MATERIALS & METHODS: We investigated the functional significance of CYP2C19*2, *3, *17 and PON1 Q192R SNPs in 89 consecutive Asian patients on clopidogrel treatment and the prevalence of functionally significant polymorphisms among 300 Chinese, Malays and Asian Indians.
  13. Lee BW, Park JG, Ha TKQ, Pham HTT, An JP, Noh JR, et al.
    J Nat Prod, 2019 08 23;82(8):2201-2210.
    PMID: 31393125 DOI: 10.1021/acs.jnatprod.9b00224
    Melicope pteleifolia has long been consumed as a popular vegetable and tea in Southeast Asian countries, including Malaysia and southern mainland China, and is effective in the treatment of colds and inflammation. In the search for active metabolites that can explain its traditional use as an antipyretic, six new phloroacetophenone derivatives (3-8) along with seven known compounds (1, 2, and 9-13) were isolated from the leaves of M. pteleifolia. Their chemical structures were confirmed by extensive spectroscopic analysis including NMR, IR, ECD, and HRMS. All compounds isolated from the leaves of M. pteleifolia (1-13) have a phloroacetophenone skeleton. Notably, the new compound 8 contains an additional cyclobutane moiety in its structure. The bioactivities of the isolated compounds were evaluated, and compounds 1, 6, and 7 inhibited tumor necrosis factor-α-induced prostaglandin E2. Moreover, the major constituent, 3,5-di-C-β-d-glucopyranosyl phloroacetophenone (1), was found to be responsible for the antipyretic activity of M. pteleifolia based on in vivo experiments.
  14. Reynor A, McArdle N, Shenoy B, Dhaliwal SS, Rea SC, Walsh J, et al.
    Sleep, 2022 Apr 11;45(4).
    PMID: 34739082 DOI: 10.1093/sleep/zsab264
    STUDY OBJECTIVES: Randomized controlled trials (RCTs) have shown no reduction in adverse cardiovascular (CV) events in patients randomized to continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea (OSA). This study examined whether randomized study populations were representative of OSA patients attending a sleep clinic.

    METHODS: Sleep clinic patients were 3,965 consecutive adults diagnosed with OSA by in-laboratory polysomnography from 2006 to 2010 at a tertiary hospital sleep clinic. Characteristics of these patients were compared with participants of five recent RCTs examining the effect of CPAP on adverse CV events in OSA. The percentage of patients with severe (apnea-hypopnea index, [AHI] ≥ 30 events/h) or any OSA (AHI ≥ 5 events/h) who met the eligibility criteria of each RCT was determined, and those criteria that excluded the most patients identified.

    RESULTS: Compared to RCT participants, sleep clinic OSA patients were younger, sleepier, more likely to be female and less likely to have established CV disease. The percentage of patients with severe or any OSA who met the RCT eligibility criteria ranged from 1.2% to 20.9% and 0.8% to 21.9%, respectively. The eligibility criteria that excluded most patients were preexisting CV disease, symptoms of excessive sleepiness, nocturnal hypoxemia and co-morbidities.

    CONCLUSIONS: A minority of sleep clinic patients diagnosed with OSA meet the eligibility criteria of RCTs of CPAP on adverse CV events in OSA. OSA populations in these RCTs differ considerably from typical sleep clinic OSA patients. This suggests that the findings of such OSA treatment-related RCTs are not generalizable to sleep clinic OSA patients.Randomized Intervention with Continuous Positive Airway Pressure in CAD and OSA (RICCADSA) trial, https://clinicaltrials.gov/ct2/show/NCT00519597, ClinicalTrials.gov number, NCT00519597.Usefulness of Nasal Continuous Positive Airway Pressure (CPAP) Treatment in Patients with a First Ever Stroke and Sleep Apnea Syndrome, https://clinicaltrials.gov/ct2/show/NCT00202501, ClinicalTrials.gov number, NCT00202501.Effect of Continuous Positive Airway Pressure (CPAP) on Hypertension and Cardiovascular Morbidity-Mortality in Patients with Sleep Apnea and no Daytime Sleepiness, https://clinicaltrials.gov/ct2/show/NCT00127348, ClinicalTrials.gov number, NCT00127348.Continuous Positive Airway Pressure (CPAP) in Patients with Acute Coronary Syndrome and Obstructive Sleep Apnea (OSA) (ISAACC), https://clinicaltrials.gov/ct2/show/NCT01335087, ClinicalTrials.gov number, NCT01335087.

  15. Ngeow YF, Hema V, Zakaria M, Lee CH, Ramachandran S
    Malays J Pathol, 1997 Dec;19(2):127-32.
    PMID: 10879253
    First-void urine samples collected from sexually transmitted diseases (STD) clinic patients were examined by a nested polymerase chain reaction (PCR) and a commercial enzyme immunoassay (IDEIA Chlamydia) for the diagnosis of Chlamydia trachomatis urethritis or cervicitis. The primers for the PCR amplified a target in the major outer membrane protein (MOMP) gene in C trachomatis while the IDEIA detected genus-specific chlamydial lipopolysaccharide. Discrepant results were resolved by retesting urine specimens with a second (plasmid-based) PCR and taking urethral or endocervical swab results into consideration. For 231 men (chlamydial prevalence 20.4%), the sensitivity, specificity, positive and negative predictive values were 59.6%, 99.5%, 96.6% and 90.6% for urine IDEIA, 68.1%, 99.5%, 97% and 92.4% for urethral swab IDEIA and 97.9%, 99.5%, 97.9% and 99.5% for urine PCR. The corresponding rates for 66 women (chlamydial prevalence 54.6%) were 19.4%, 100%, 100% and 50.8% for urine IDEIA, 86.1%, 96.7%, 96.9% and 85.3% for endocervical swab IDEIA and 91.7%, 93.3%, 94.3% and 90.3% for urine PCR. Hence, in a high prevalence population, the urine IDEIA was a suitable alternative to the male urethral swab IDEIA but significantly less sensitive than the endocervical swab IDEIA. The urine PCR was, however, much more sensitive than the urine IDEIA for both men and women and could replace the endocervical swab IDEIA for the diagnosis of chlamydial cervicitis.
  16. Chan KH, Lee CH, Sharif SZ, Hayati F, Sallapan S
    Ann Med Surg (Lond), 2020 Dec;60:438-441.
    PMID: 33251002 DOI: 10.1016/j.amsu.2020.11.035
    Background: Metastatic neuroendocrine tumours (NETs) to the breast are very rare entities.

    Case presentation: A 26-year-old lady presented with anterior neck swelling with symptoms of superior vena cava syndrome for 6 months. Imaging study revealed a mediastinal mass which was preceded with core biopsy which was consistent with high-grade small cell NETs. Despite second-line adjuvant chemotherapy and radiotherapy, her disease became advanced which was confirmed via restaging scan. There were bilateral breast lesions discovered during the scan which was deemed to be metastatic NETs histologically. Despite prompt initiation of treatment, she succumbed 1 year after the radiotherapy due to disease progression.

    Conclusion: High suspicion of an index is needed for diagnosis when patients with known primary NETs present with suspicious breast lesions. Triple assessment is mandatory, however histopathology assessment and immunohistochemistry staining are the mainstay of diagnosis.

  17. Lee CH, Hayati F, Azizan N, Sharif SZ
    Iran J Otorhinolaryngol, 2023 Nov;35(131):325-328.
    PMID: 38074483 DOI: 10.22038/IJORL.2023.73099.3471
    INTRODUCTION: Ectopic thyroid is an uncommon condition resulting from the aberrant development of the normal thyroid gland and is usually found along the thyroglossal tract: lingual, submandibular, thyroglossal cysts, intra-tracheal and mediastinal, or, on rare occasions, in the adrenal gland, gallbladder, gastrointestinal tract, pancreas, and struma ovarii.

    CASE REPORTS: We describe a novel case where primary papillary thyroid carcinoma (PTC) was found after a trans-oral excision of a tumor containing ectopic thyroid tissue at the posterior pharynx, an area not known to be a location for ectopic thyroid. Delays due to the COVID-19 pandemic resulted in regional cervical metastases and multifocal PTC. The female patient successfully underwent total thyroidectomy, selective cervical and central lymph node dissection, followed by adjuvant radioactive iodine ablation, with no evidence of distant metastases.

    CONCLUSIONS: Ectopic thyroid tissue is uncommon and may be in the posterior pharynx. The principles of management remain those of differentiated thyroid malignancy: complete surgical resection of any tumor focus, total thyroidectomy, and node dissection of involved lymph nodes, followed by adjuvant radioactive iodine in iodine-sensitive tumors.

  18. Lee TH, Wani WA, Lee CH, Cheng KK, Shreaz S, Wong S, et al.
    Front Pharmacol, 2021;12:626233.
    PMID: 33953670 DOI: 10.3389/fphar.2021.626233
    Edible Bird's Nest (EBN) is the most prized health delicacy among the Chinese population in the world. Although some scientific characterization and its bioactivities have been studied and researched, no lights have been shed on its actual composition or mechanism. The aim of this review paper is to address the advances of EBN as a therapeutic animal bioproduct, challenges and future perspectives of research involving EBN. The methodology of this review primarily involved a thorough search from the literature undertaken on Web of Science (WoS) using the keyword "edible bird nest". Other information were obtained from the field/market in Malaysia, one of the largest EBN-producing countries. This article collects and describes the publications related to EBN and its therapeutic with diverse functional values. EBN extracts display anti-aging effects, inhibition of influenza virus infection, alternative traditional medicine in athletes and cancer patients, corneal wound healing effects, stimulation of proliferation of human adipose-derived stem cells, potentiate of mitogenic response, epidermal growth factor-like activities, enhancement of bone strength and dermal thickness, eye care, neuroprotective and antioxidant effects. In-depth literature study based on scientific findings were carried out on EBN and its properties. More importantly, the future direction of EBN in research and development as health-promoting ingredients in food and the potential treatment of certain diseases have been outlined.
  19. Ayu RS, Khalina A, Harmaen AS, Zaman K, Mohd Nurrazi N, Isma T, et al.
    Sci Rep, 2020 01 24;10(1):1166.
    PMID: 31980742 DOI: 10.1038/s41598-020-58278-y
    In this study, it focused on empty fruit brunch (EFB) fibres reinforcement in polybutylene succinate (PBS) with modified tapioca starch by using hot press technique for the use of agricultural mulch film. Mechanical, morphological and thermal properties were studied. Mechanical analysis showed decreased in values of modulus strength for both tensile and flexural testing for fibres insertion. Higher EFB fibre contents in films resulted lower mechanical properties due to poor fibre wetting from insufficient matrix. This has also found evident in SEM micrograph, showing poor interfacial bonding. Water vapour permeability (WVP) shows as higher hydrophilic EFB fibre reinforcement contents, the rate of WVP also increase. Besides this, little or no significant changes on thermal properties for composite films. This is because high thermal stability PBS polymer show its superior thermal properties dominantly. Even though EFB fibres insertion into PBS/tapioca starch biocomposite films have found lower mechanical properties. It successfully reduced the cost of mulch film production without significant changes of thermal performances.
  20. Ahmad Saffian H, Hyun-Joong K, Md Tahir P, Ibrahim NA, Lee SH, Lee CH
    Materials (Basel), 2019 Dec 05;12(24).
    PMID: 31817323 DOI: 10.3390/ma12244043
    In this study, the effects of lignin modification on the properties of kenaf core fiber reinforced poly(butylene succinate) biocomposites were examined. A weight percent gain (WPG) value of 30.21% was recorded after the lignin were modified with maleic anhydride. Lower mechanical properties were observed for lignin composites because of incompatible bonding between the hydrophobic matrix and the hydrophilic lignin. Modified lignin (ML) was found to have a better interfacial bonding, since maleic anhydrides remove most of the hydrophilic hydrogen bonding (this was proven by a Fourier-transform infrared (FTIR) spectrometer-a reduction of broadband near 3400 cm-1, corresponding to the -OH stretching vibration of hydroxyl groups for the ML samples). On the other hand, ML was found to have a slightly lower glass transition temperature, Tg, since reactions with maleic anhydride destroy most of the intra- and inter-molecular hydrogen bonds, resulting in a softer structure at elevated temperatures. The addition of kraft lignin was found to increase the thermal stability of the PBS polymer composites, while modified kraft lignin showed higher thermal stability than pure kraft lignin and possessed delayed onset thermal degradation temperature.
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